Help please need advise!!

I went to the hospital because of some bright red bleeding and some cramps I immediately went in because I miscarried back in August too I'm supposed to be 8 weeks I went for ultrasound I had a sac w no baby visible measuring at 5weeks 3 days. They sent me home bed rest no intercourse said my hgc levels were okay I was just measuring earlier..... is it really possible to have such a big difference In time frame? I'm still bleeding I have so many mixed emotions. anyone else gave this happen to them?