Tengo problemas al subir imagenes a mi base de datos

para obtener la identificación del producto

$query=mysqli_query($con,"select max(id) as pid from products");
$result=mysqli_fetch_array($query);
$productid=$result['pid']+1;
$dir="productimages/$productid";
if(!is_dir($dir)){
mkdir("productimages/".$productid);
}

move_uploaded_file($_FILES["productimage1"]["tmp_name"],"productimages/$productid/".$_FILES["productimage1"]["name"]);
move_uploaded_file($_FILES["productimage2"]["tmp_name"],"productimages/$productid/".$_FILES["productimage2"]["name"]);
move_uploaded_file($_FILES["productimage3"]["tmp_name"],"productimages/$productid/".$_FILES["productimage3"]["name"]);

$sql=mysqli_query($con,"insert into products(category,subCategory,productName,productCompany,productPrice,productDescription,shippingCharge,productAvailability,productImage1,productImage2,productImage3,productPriceBeforeDiscount) values('$category','$subcat','$productname','$productcompany','$productprice','$productdescription','$productscharge','$productavailability','$productimage1','$productimage2','$productimage3','$productpricebd')");
$_SESSION['msg']="Producto insertado con éxito !!";

}


?>

Editado