I need some serious advice?

Steroids and some antibiotics can miss with a period. I happen to get stripe throat a few years ago and had to take steroids and it made my period over a mouth late. i knew i wasn't pregnant because i was Single and not having . But then again you could be pregnant. I would wait 3-7 days and if no period take a hpt, or contact your doctor and get a blood test. I wish you the best of luck.