So annoyed with my periods

My periods are super random even on birth control i havent had a proper period since the summer. On Halloween i got a trick i spotted for like 30mins and then my 'period' was done. I had sex with my boyfriend on Christmas then on boxing day i had light spotting all day but none of it got on my panty liner only there when i wipe. then today its gone like nothing happened but i still have all the period symptoms just no blood ughhh i hate it!!!😭