you could be pregnant!
Antibiotics effect birth control negatively. Yes, if your breast are sore and numb and you are having unprotected sex while taking antibotics and birth control then chances are 99% that you are...
No some early or late periods are normal.
Some women experience breakthrough bleeding while on The Pill - most commonly in the first 3 months.
the pill has so many side effects listed that you should read the label for side effects