Hello,
Antibiotics can effect the birth control pills efficacy and since you have recently started them , you should use additional contraception like condoms to prevent pregnancy.
It is very difficult to precisely confirm a diagnosis without examination and investigations and the answer is based on the medical information provided. For exact diagnosis, you are requested to consult your doctor. I sincerely hope that helps. Take care and please do keep me posted on how you are doing.
Been there done that and I got pregnant! Use another form of protection along with your pill whenever you are on antibiotics.