Confused please answer

Va

So I had protected sex almost 4 weeks ago, my period came later not that much as usual but it was normal, and after that I’ve been having cramps, my vagina is swollen as same as my stomach and little headaches.

I recently changed my birth control pills and also am taking an antibiotic for acne.

Should I worry bout something?

Or this can be ovulation?

I need some answerssss