Hello.,I Had Been Taking Uti Medications Until End Of My

Hello.,I had been taking uti medications until end of my last menstrual flow.thereafter I had unprotected sex 5 days after ovulating.however we used withdrawal.had unprotected sex again four days before my menstrual flow.I am 3 days down and not yet received my periods.no pregnancy symptoms however.is it early for a test and might it be something else?