Constantly paranoid about being pregnant?

okay so i've been on birth control for over 6 months now. i haven't had sex a lot in the past few months, due to me and my boyfriend breaking up. we recently got back together & had sex for the first time about a week ago. i guess since i'm mentally aware of having sex again, i'm more paranoid about the possibility of being pregnant. it seems irrational almost considering i take my pill everyday on time (give or take 30 minutes) & i know i haven't missed or skipped a pill in my last pack because i labeled the days accordingly and would have easily seen if i has forgotten a day's pill. i'm already 3 days into my placebo pills & i take my 4th one tonight at 10pm. i keep worrying that i'm just not going to get my period. i've already been constantly peeing this morning but i think i have a UTI (i've already had 3 before so the feeling is sort of familiar). the night me and my boyfriend had sex, he pulled out & i was already fairly certain that i had kept up with my pill taking very well. but now that i'm so close to my period, & it's not here yet, i keep thinking "what if" i messed up on one day & it ruined everything? & since it's only been a week since the last time i had sex, i highly doubt im experiencing any symptoms. i'm pretty sure it's all in my head. do you think i'm being paranoid & overreacting? & that i should just wait until the end of my placebos for my period to come? i know it's a bit early but i'm going to buy a pregnancy test (the one that tests 6 days before a missed period) after work & take one in the morning to ease my mind :)