Birth Control

This is my second month on birth control , and I've been taking my pills regular. (At 9 each morning) but during the first week I forgot to take Tues-Thursday but I just doubled up, and continued I was back on track. My period came on the 15th last month , so it said this time around it should come on the 12th which it didn't , so should it be here by the 15th? I'm a little concerned , and my bf n I had unprotected sex. Should I be worried ?