Period clumps

Ok I know this is kind of gross, because my own blood is grossing me tf out. I started taking birth control pills three weeks ago. The first two weeks where great. I was having a lot of sex with my boyfriend and everything was 🤟🏼. But out of no where I started bleeding in the beginning of the third week. And I’m like ok it’s a little period even though I’m not on the placebos. But I’ve been bleeding for like 5 days and it’s not getting lighter and every time I wipe it’s just a heavy flow and clumps of blood. It could be that the day I started taking birth control was the day I was supposed to start my period so it didn’t let any blood out for an extra to weeks. Idk but these camps and mood swings are killing me.