At the bottom of look: you have RETURN listed twice.

You turn TMR1 Off (T1CON = 0) in your Disp: Interrupt Handler but I don't see where you turn it back on.

"segment = value/1000
gosub look
thousands=segment ; extract thousands"

Leads right into your look: Interrupt Handler. If that was to be a subroutine, you need that extra RETURN relocated to the end of that grouping.