Crazy discharge!

Yes this is tmi .. but I just wiped and I HUGE ASS discharge came out , in tact and stuff .. I just got off my period like 2 days ago , and last night I had sex with my boyfriend and yes he did finish inside of me .. I have the Mirena IUD and idk if that had to do with anything .. I cannot take a plan b because it can mess with my IUD and hormones ..

what do you think this is?