Hi Well My Problem Is I've Been Having Active Sex

Hi well my problem is I've been having active sex lately unprotected and eveytime I'm done I have really bad blood my period was a week and 2 days late before the bleeding and now I'm really nausea and I have really bad cramps! I don't know what's going on and I have discharge for the first time and like liquids coming out of my vaginal I think it's a miscarriage but I don't know..