I would have the doctor run a blood test on you sweetie.
HPT tests all trace the amount of a special hormone in your body called hCG (Human Chronic Gonadotropin). When you take home tests it just tracks what’s in your urine stream. If 3 of the 4 tests have come out positive, it very well possible could be pregnancy. If they had you urinate on one of their sticks, there’s might have been expired (Can you believe they have expiration dates?!?! O.o ) So I would definitely go for a blood test! It will be the most accurate.
Good luck and please keep us posted!