I've been on Tri-Sprintec birth control for almost 4 years, my boyfriend and I always use condoms except about 9 days ago we didn't and I've been worrying myself sick as to if I could possibly be pregnant. I've had spotting today but I'm thinking it's because of stress, I'm literally making myself nauseas. I never miss a pill if anything I've only ever taken maybe 2 pills a couple hours late this pack so far.