Confused please help

So I was pregnant but my HCG was low. It went from 15 to 44 to 92 then 27. When it dropped last week, I was told not a viable pregnancy and will be a miscarriage. I started bleeding Saturday and just stopped today which I assume was the miscarriage. My question is I was only 4 weeks 5 days pregnant as of Saturday. This entire week I have been extremely emotional, high anxiety and stress levels, and extremely nauseous. Smell and thought of some food literally is making me gag. I have thrown up twice because of smells. All of this is out of character for me. I am not an emotional person and I love all food way to much. If I didn't know better I would say I was still pregnant. Anyone else experience something like this?