on my 3rd month of taking birth control and yesterday i experienced brown discharge and it’s carried on today. i had sex a few days prior to this and it really hurt me at the start (unusual) i take the pill religiously and and we use condoms what could this be?

Hey, maybe you're just spotting, which is a common side effect of the pill, or you got some micro tears in your vagina from sex since you said it hurt. If it's spotting it can last from days to weeks, but if you got injured during sex the bleeding should stop soon in the next few days. I suggest you check if you have any wounds or skin tearings down there, then you will know for sure.