ugh!!

Okay y'all I know I've been posting quite a bit, but now I'm even more confused. Please read and give me your HONEST opinions. So last Friday I went the the ER due to bleeding and cramping, where I was told they found two sacs but that my HCG had dropped from 800 down to below 100, well I went to my OB Monday where he said a dnc wasn't necessary because my urine test came back negative, so I dealt with it and finally started getting okay......here's where it gets even more weird. Thursday I took a pregnancy test and it came back POSITIVE, so yesterday (Friday) I got a positive digital. So I ended up back at the ER because my cramping was terrible, where they told me that my levels should have been down to 0 on my blood work, but they went back up to 300, I'm just so confused at what could be going on. The ER doc says she thinks I could still be pregnant, but I don't see how considering I'd be 7 weeks 1 day, and my HCG should be way more than 300 right?? Can anyone help please!! I don't go to my OB until Monday and I'm going crazy!!