TMI - BLOOD CLOT??? ( please help )

Okay so I have had 2 pregnancies that ended up being a chemical miscarriage both around 5/6 weeks no one really knows how far along I was. I have finally got my period after 2 1/2 months not having my period I thought maybe it was from the Depo shot (first time having it so I am safe for my surgery that is coming up) anyways my period started today, really heavy I looked into the toilet and there was a clot the size of maybe two fingers in width. I wiped and it looks like a dark red/black I showed my partner and he says to call my gp tomorrow but I can’t wait that long. I just need an opinion now or maybe to ease my conscious.