pregnancy?

I'm only 16, I'm taking the pill and have been for a few months , I've been with my boyfriend for almost 3 years and he's 19.... the last month I let him finish in me because well I know so many people who have done it while on BC and haven't fallen pregnant, I take it every day at the same time and I don't miss any, I'm about to take my "sugar pill" tonight but the last 2 days I've had really thick egg white mucus, almost or is clear and it feels like egg white also, this morning I've felt like I need to vomit but I held it in... I know it's silly to let him finish in me but is there a chance I'm pregnant? I'm about to drive to the shops and take a test... please no hate I just need advice