Emergency contraceptive taken, still no period!! ?pregnant?

I have been on oral contraceptives for years. I was taking the first week of the active pills of a new cycle when I was diagnosed with a kidney infection. I had to take a 3 week course of cephazolin, trimethoprim and amoxicillin. I finished this course at the end of the 3rd week of active pills. I took the 4th week of active pills at the correct time and I didn't have sex. I started my first sugar pill on Saturday and I had unprotected sex on Sunday (lasted for 30 seconds, my bf didn't cum). I was worried so I took the morning after pill an hour after sex. I was supposed to get my period on the 4th sugar pill, I'm on the 5th sugar pill and still no period!! I'm worried that I may be pregnant! Please help!