Does contraceptive pills cause lower abdominal cramps, spotting, and bloating?

Hi doctor,

Two weeks before my boyfriend and I had an unprotected sex. I am 100 percent sure he did not ejacuate in me. Just to be safe, I took tablet Plan B a couple of hours after intercourse. I have no clue if I was ovulating or if I had already ovulated becaude my periods are irregular. My last period started before four week, and they usually last around eight days. Around two to three days after taking the Plan B, I started to develop lower stomach cramps. Then on days three to four I started to have spotting, and now it is day eight and I am still bleeding. Throughout these past few days I have been having cramps and I have been bloated. Do you think these are all just symptoms of Plan B or could this be my period? Does this mean the Plan B worked? What do you think about my chances of pregnancy? Is there anything else I should do? Thank you.