am I having a miscarriage?

so, I thought I was pregnant for the passed couple weeks. I've had nausea, dizziness, even what seemed like implantation bleeding. I bled very light pink blood on and off for almost 2 days about 2 weeks ago. about 3 or 4 weeks prior I had unprotected sex on my period where my partner finished inside me. now Glow said my period is supposed to come tomorrow, and last night before i fell asleep around 10 i noticed a very little light pink blood when i wiped, but at 4 am I woke up in a sweat, with severe cramping, and a very very heavy flow with dark red almost black looking clumps coming out. a little over 12 hours and my blood is still heavy and bright red with clumps still coming out. the abdominal cramping got so bad earlier today that walking was hard. I have not felt nausea at all today or any dizziness. I was going to wait until Friday, two days from now, to take a pregnancy test. just to be sure it wouldn't be too early, but now I fear I am having a miscarriage. my period has never been this painful, bloody, or ever clumps like this. am I over reacting? should I go to a doctor? I'm just very worried. **edit I also got VERY bloated throughout this time. like I look like gained weight everywhere and I know I have not because my diet has been minimal as of lately due to wanting to lose weight