What is wrong with me?

I had sex on the 12th of this month. The day after I got a bit of spotting and it keeps up so I assumed it was my period. But I didn’t have any cramping associated with it so I thought that was odd. Last night I had felt sick and my stomach was tight as fuck like upper part of my stomach. Next day. The stomach tightening is still here. And I’m nauseous. I’m lightly bleeding still so I’m just wondering what other people think.