Miscarriage?

Lhea
I just found out I am pregnant, had a blood test to confirm. Only 4 weeks 3 days. So very early. But today I started bleeding, not just spotting. Went to the ER, did bloodwork HCG level same as yesterday (still low). Ultra sound showed nothing. They basically said they can't tell me anything and to follow up with my OB next week. I don't know what to think..