Could I Be Pregnant With Brown Water Like Discharge After Period?

Okay I'm 20 years old and I've always had a very irregular period. Maybe every three months, but not to be exact, it's so random. I went home from college for 5 weeks. My first week there I had my period. Then my last week there I had unprotected sex twice (and he finished in me twice) I went back home to college. About 10 days later I was feeling nauseous for 2 days and then I had spotting.. But then the next day I started bleeding really bad but with clotting. I would've thought it was a normal period if it weren't for the clots and how heavy it was. I thought it was a miscarriage.. I bled heavy for 3 days and after it was done now I have brown water like discharge.. Could I still be pregnant or is there any cause of this?