Stock Location If Statement

Stock Location If Statement

I have two forms, Inventory and Parts Used.
In the Inventory form, I have 12 stock location for each Part. That form is updated when Parts are received from Purchase orders.
When my Technicians use a part (From the Parts Used Form), the quantity is reduced in the Inventory Form for their location, there for maintaining a stock level. I am trying to create a script, that when they select the part, enter a quantity, their location, it checks to insure they have inventory in their location.
I have listed the script built, but, it only checks the first location entry.

Any ideas on how to fix? 

My theory was to Fetch the part number from the Inventory, if the location selected was "<=0", then send an "Alert" and "Cancel Submit"
see below;

qty  =  Inventory  [Product_Number == input.Part_Number1];
loctrk1= (qty.trk1  -  input.trk1);
loctrk2 = (qty.trk2  -  input.trk2);
loctrk3= (qty.trk3 -  input.trk3);
loctrk4 = (qty.trk4  -  input.trk4);
loctrk5 = (qty.trk5  -  input.trk5);
loctrk6 = (qty.trk6  -  input.trk6);
loctrk7 = (qty.trk7  -  input.trk7);
loctrk8= (qty.trk8  -  input.trk8);
loctrk9= (qty.trk9  -  input.trk9);
loctrk10 = (qty.trk10  -  input.trk10);
loctrk11 = (qty.trk11  -  input.trk11);
loctrk12= (qty.trk12  -  input.trk12);
loctrk13 = (qty.trk13 -  input.trk13);
loctrk14= (qty.trk14  -  input.trk14);
loctrk15= (qty.trk15  -  input.trk15);
if (loctrk1 <=  0)
{
    alert "You have" + " " + qty.trk1 + " " + "in stock, Please choose another location. Thank You";
    cancel submit;
}
if (loctrk2  <=  0)
{
    alert "You have" + " " + qty.trk2+ " " + "in stock, Please choose another location. Thank You";
    cancel submit;
}
if (loctrk3  <=  0)
{
    alert "You have" + " " + qty.trk3+ " " + "in stock, Please choose another location. Thank You";
    cancel submit;
}
if (loctrk4  <=  0)
{
    alert "You have" + " " + qty.trk4 + " " + "in stock, Please choose another location. Thank You";
    cancel submit;
}
if (loctrk5  <=  0)
{
    alert "You have" + " " + qty.trk5+ " " + "in stock, Please choose another location. Thank You";
    cancel submit;
}
if (loctrk6 <=  0)
{
    alert "You have" + " " + qty.trk6 + " " + "in stock, Please choose another location. Thank You";
    cancel submit;
}
if (loctrk7  <=  0)
{
    alert "You have" + " " + qty.trk7 + " " + "in stock, Please choose another location. Thank You";
    cancel submit;
}
if (loctrk8 <=  0)
{
    alert "You have" + " " + qty.trk8 + " " + "in stock, Please choose another location. Thank You";
    cancel submit;
}
if (loctrk9  <=  0)
{
    alert "You have" + " " + qty.trk9 + " " + "in stock, Please choose another location. Thank You";
    cancel submit;
}
if (loctrk10  <=  0)
{
    alert "You have" + " " + qty.trk10 + " " + "in stock, Please choose another location. Thank You";
    cancel submit;
}
if (loctrk11  <=  0)
{
    alert "You have" + " " + qty.trk11+ " " + "in stock, Please choose another location. Thank You";
    cancel submit;
}
if (loctrk12 <=  0)
{
    alert "You have" + " " + qty.trk12+ " " + "in stock, Please choose another location. Thank You";
    cancel submit;
}