Questions... help?

Alright y’all, here’s my problem:

My period is 8 days late, and it’s never late. I am sexually active. I’m on birth control and we use condoms every single time. For a bit I was on pain killers and muscle relaxers. Today I just took my last dose of an antibiotic for a UTI. I’m a full time college student with exams coming up this friday.

So, is it stress delaying my period or something else?