no period yet... pregnant?

Madi

ive been on sronyx birth control (a 28 day cycle pill) for 7 months. i’m only 16, so birth control is a big deal to me. i really don’t want any babies right now, i take it at the same time every day, store it correctly in room temperature, take it with no other medications, and haven’t had an upset stomach. also, i know it’s not reliable on its own, but my boyfriend always pulls out. even though i’m on the pill, i don’t trust it enough for him to cum inside me. i use it continuously so i’ve only ever had one “period” on birth control after continuously taking active pills for 3 months. this cycle i tried to skip 4 months, but at the 3 month mark i had breakthrough bleeding that lasted for 13 days. it started out as pink / light brown, but then quickly turned into a combination of red, dark brown, and almost black. it looked like very very old blood if you ask me. it resembled a period in the sense that it was very heavy, came with minor cramps, and got heavier when i exercised. it was just weird because i was taking active pills during that time. that bleeding all started about 4 days after the last time i had sex and lasted for an annoying 13 days. it’s about a week and a half later, and i just started my placebo week of pills (4 month mark.) i’m a little nervous. i’m on my second day of placebo pills (i just took it 5 minutes ago), and nothing has happened. i haven’t bled at all yet. this is a little nerve wracking for me because since my last “period” in march, i started becoming sexually active. this means i haven’t experienced a period since i’ve started having sex. i don’t really feel any pregnancy symptoms aside from the sore boobs i felt yesterday (first day of inactive pills). i also did experience some nausea during the 4th month of my active pills, but i think that was because my body wasn’t used to having hormones for 4 months straight. since starting the placebo week, my nausea has disappeared. i’m just worried my period hasn’t started yet. i has some thick white discharge yesterday, is this a sign my period is coming? it wasn’t stringy, but it was very think, almost like yogurt. do you think that episode of breakthrough bleeding will throw off my period, even though it was old blood? is this normal? should i test? help!