Pregnancy symptoms coming back after miscarriage

I had a miscarriage about 3 weeks ago. My doctor told me that my period probably wouldn’t come on for a month or 2. My breast were sore and I was a little nauseous all of last week, from the 11th-20th I had sex 3 times so I thought maybe I could be pregnant but I had my blood drawn at my follow up appointment on Tuesday and my hcg levels are back down to 0. I figured that I was just paying too much attention and the symptoms would just disappear. But now I’m even more confused because yesterday my nausea became worse and I became sleepier than before. After eating I had no energy at all and I just wanted to go to sleep, the symptoms aren’t calming down today either. Has anybody had their symptoms come back so heavy 3 weeks after a miscarriage and not be pregnant at all?