My boyfriend ejaculate in me and I haven't finished a pack of tri-cyclen lo yet. This is my first month taking birth control pills. I take them regularly at the same time every day, without missing one. It's my third week, is there a chance I could get pregnant?

I am still taking them, and before having sex with my boyfriend I noticed spotting on my pantie. I had cramps the whole day before having sex and still am feeling cramps. Please help.