How likely am I to be pregnant?

My period is 7 days late, I messed up on my birth control 4 months ago (I missed a month of pills) but my period was only affected just last month with a 11 day period. Now I'm a week late and in worried for being pregnant. I've used the pill correctly lately, but I'm having cramps and my boyfriend and I haven't been using condoms. (He does the pull out method, which is stupid, but I thought the pill would be effective enough). So how likely is it that I'm pregnant?