can being more sexually active affect my period?

Not really sure what's going on with me, I used to get my period every 28 days, would always know when I was going to get it. 
I stopped by birth control in like May? And it stayed that way throughout most of the summer.
Now this month and last month I have gotten it much sooner than usual. Last month it was 21 days and this month 19 days. 
I'm thinking it's probably the birth control thing, but I was wondering if being more intimate now is affecting that as well. This past night I was rather intimate with my SO and then I got my period about an hour after we stopped. TMI but I went to the bathroom to pee and a huge blob of blood came out as well... could that be related?