Whats up with my cycle? Light period, now clots?

So I've always had a pretty average menstrual cycle every month and I've been on birth control pills for the past couple years, with everything being fine. Last month my period was a few days late and then very light and spotty for a couple days but with killer cramps, both being very unusual for me. I took a pregnancy test before I started my next months pills to be safe and it was negative. I had a few normal weeks on the pill besides a bit of dizziness. I am on my week off waiting for my period, I had a very light brown creamy discharge for a few days and now some brown spotting. I just went to the bathroom and there was a clot about the size of the end of your pinky and some brown discharge. I've been having bad cramps like last month and I've never really ped a clot before. Even though it was small it still concerns me as it was grayish/pink and bright red. But still no real blood. Any ideas what up?