Ha I'm 17 i am on the pill but I have also been sick and taking antibiotics and ibuprofin so i knoww the pill gets canceled out. I have been having some really bad cramps on my lower right side. I feel bloated and get dizzy a lot. I have cramps like period cramps but I'm not due for my period till early march. My back hurts like crazy and around 10 pm
Antibiotics don't completely cancel out the pill, but you do need to use protection while on the pill and antibiotics.
I would say the best thing for you to do take a test if you are worried, I might be to early since you haven't missed your period yet. You can get a cheap pregnancy test at the dollar store ( I get mine there) and they are just as accurate as the more expensive ones.
Your symptoms could be your period on its way or maybe some side effect to what ever antibiotic you are taking.
But always, When your not sure, take a test! And be sure to tell your parents if you are in fact pregnant!!!!!!!!!!!!!!!!!!!1