What to expect?

So I am supposed to be 7 weeks pregnant today, but dr confirmed yesterday that my hcg is declining. This was my first pregnancy. I dont know what to expect for my miscarriage. I've been bleeding since Christmas Day. I had heavy bleeding for a few hours last week, but otherwise I fill a pad every 12 hours or so. I've been passing tiny bits of tissue. Then last Monday I had horrible cramps, it woke me up in the middle of the night. Felt like I needed to go to the bathroom, sat on the toilet for awhile nothing came. But when I wiped there was a clot on the tp. It was about the size of the cotton part of a q-tip. It was oblong shaped and had a jelly like consistency with a white sac on one end. The bleeding is minimal now, it stopped yesterday. Then today there is a lil bit. I'm just wondering how long I will bleed, if I will pass a big clot, horrible pain.. idk what to expect here.