แบ่งหน้าไม่ถูกต้องครับ หน้าแรกและหน้าสุดท้ายปกติ แต่หน้า 2 3 ... จะ *2 จากจำนวนต่อหน้าที่กำหนด

<?php
					 		$nb = $db->prepare('SELECT * 
					 							   FROM tbl_machine 
					 			                    WHERE list LIKE :keyword
					 							            ORDER BY machine_id ASC');
					 		$nb->bindParam(':keyword',$keyword, PDO::PARAM_STR);
					 		$nb->execute();
					 		$num_rows = $nb->rowCount();

					 		$per_page = 15;   // Per Page
  							$page  = 1;
  
  							if(isset($_GET["Page"])){
    							$page = $_GET["Page"];
  							}

  							$prev_page = $page-1;
  							$next_page = $page+1;

  							$row_start = (($per_page*$page)-$per_page);
  							if($num_rows<=$per_page){
    							$num_pages =1;
  							}
  							else if(($num_rows % $per_page)==0){
    							$num_pages =($num_rows/$per_page) ;
  							}
  							else{
    							$num_pages =($num_rows/$per_page)+1;
    							$num_pages = (int)$num_pages;
  							}
  							
  							$row_end = $per_page * $page;
 							if($row_end > $num_rows){
    							$row_end = $num_rows;
  							}

  							$nb = $db->prepare('SELECT tbl_machine.list,tbl_machine.code,tbl_machine.type,tbl_machine.status,tbl_machine.machine_id,tbl_type.type 
					 							  FROM tbl_machine 
					 							  INNER JOIN tbl_type ON tbl_machine.type=tbl_type.id
					 			                  WHERE list LIKE :keyword
					 							  ORDER BY machine_id ASC
					 							  LIMIT :row_start ,:row_end');
					 		$nb->bindParam(':keyword',$keyword, PDO::PARAM_STR);
					 		$nb->bindParam(':row_start', $row_start, PDO::PARAM_STR);
            				$nb->bindParam(':row_end', $row_end, PDO::PARAM_STR);
					 		$nb->execute();
					 ?>
					 	<table class="table table-striped table-bordered" id="manage">
					 		<thead>
					 			<!-- <th style="text-align: center;">
									<input type="checkbox" value="" name="chkAll" id="chkAll">
								</th> -->
					 			<th style="text-align: center;">#</th>
					 			<th style="text-align: center;" class="headerSortUp">ชื่อเครื่อง</th>
					 			<th style="text-align: center;" class="headerSortUp">รหัสครุภัณฑ์</th>
					 			<th style="text-align: center;" class="headerSortUp">หมวดหมู่</th>
					 			<th style="text-align: center;" class="headerSortUp">สถานะเครื่อง</th>
					 			<th style="text-align: center;">จัดการ</th>
					 		</thead>
					 		<?php
					 		$i=1;
					 		if($page > 1){
                  						$i = ($per_page * ($page-1)) + 1; 
                			 	}
					 			while ($row = $nb->fetch(PDO::FETCH_ASSOC)) {
					 				if ($row['status'] == 'idle') {
					 					$status = 'ว่าง';
					 				}
					 				elseif ($row['status'] == 'busy') {
					 					$status = 'ถูกใช้งาน';
					 				}
					 				else {
					 					$status = 'ซ่อม';
					 				}
					 		?>
					 		<tbody>
					 			<tr>
					 				<!--<td style="text-align: center;">
										<input type="checkbox" name="chkDelete[]" id="chkDelete" value="<?=$row['machine_id'];?>" >
									<!--</div>
					 				</td>-->
					 				<td style="text-align: center;"><?php echo $i; ?></td>
					 				<td style="text-align: center;"><?php echo $row['list']; ?></td> 
					 				<td style="text-align: center;"><?php echo $row['code']; ?></td> 
					 				<td style="text-align: center;"><?php echo $row['type']; ?></td>
					 				<td style="text-align: center;"><?php echo $status; ?></td>
					 				<td style="text-align: center;">
					 					<a name="btnView" id="btnView" type="button" class="btn btn-info btn-xs" href="view-parcel?id=<?=$row['machine_id'];?>"><span class="glyphicon glyphicon-eye-open" aria-hidden="true"></span> ดู</a>

					 					<a name="btnUpdate" id="btnUpdate" type="button" class="btn btn-warning btn-xs" href="update-parcel?id=<?=$row['machine_id'];?>"><span class="glyphicon glyphicon-refresh" aria-hidden="true"></span> แก้ไข</a>

					 					<a name="btnDanger" id="btnDanger" type="button" class="btn btn-danger btn-xs" data-toggle="modal" data-target="#confirm-delete" data-href="<?php echo $_SERVER["PHP_SELF"];?>?Action=Delete&del=<?php echo $row["machine_id"];?>" ><span class="glyphicon glyphicon-remove" aria-hidden="true"></span> ลบ</a>

					 				</td>
					 			</tr>
					 		<?php
					 		$i++;
					 			} //end while
					 		?>
					 		</tbody>
					 	</table>
					 		<br>
              			ทั้งหมด <?php echo $num_rows;?> รายการ

              			<nav aria-label="Page navigation">
                			<ul class="pagination pull-right" style="margin-top:0;">
                  		<?php
                    		if($prev_page){
                      			echo " <li><a href ='$_SERVER[SCRIPT_NAME]?Page=$prev_page&txtKeyword=$strKeyword'><span aria-hidden='true'>Back &laquo;</span></a></li> ";
                    		}

                    		for($i=1; $i<=$num_pages; $i++){
                      			if($i != $page){
                        			echo "<li> <a href='$_SERVER[SCRIPT_NAME]?Page=$i&txtKeyword=$strKeyword'>$i</a> </li>";
                      			}
                      			else{
                        		echo "<li class='active'><a href='#'> $i <span class='sr-only'>(current)</span></a></li>";
                      			}
                    		}  

                    		if($page!=$num_pages){
                      			echo " <li><a href ='$_SERVER[SCRIPT_NAME]?Page=$next_page&txtKeyword=$strKeyword'><span aria-hidden='true'>Next &raquo;</span></a></li> ";
                    		}
                  		?>
                			</ul>
              			</nav>

              			<div class="col-lg-1 pull-right">
                			<select name="ddlPage" class="form-control" onchange="javascript:window.location='?Page='+this.options[this.selectedIndex].value+'&txtKeyword=<?php echo $strKeyword;?>';">
                  			<?php
                    			for($x=1; $x<=$num_pages; $x++){
                  			?>
                    		<option value="<?php echo $x;?>" <?php if($page==$x){echo "selected";}?>> <?php echo $x;?> </option>
                  			<?php
                   				}
                  			?>
                			</select>
              			</div>