Bleeding for 5 days .

I started lightly spotting on Sunday night and Monday I went to the ER. They couldn’t find the cause and just monitored me for a little while then sent me home. I very lightly spotted only at night Tuesday Wednesday. Thursday night I felt a gush and thought it was discharge till I went to the restroom and saw I bleed through my shorts. I bleed quiet a lot that night but felt no discomfort what’s so ever. It’s now Sunday and I’m still spotting. I have an OB appt on Tuesday. But I’m concerned about it at this point. I’m 16 weeks pregnant.