Chemical pregnancy? Miscarriage?

Last week I got several positive pregnancy tests. This being the last one I took as confirmation. As of Sunday morning I woke up bleeding pretty heavily. Called my doctor Monday morning and was advised to go to the ER. Upon arrival and blood work I was told my blood test came back with a 1 hcg level. The nurse stated even if I was pregnant and started to miscarry Monday than the levels would have been higher. She mentioned chemical pregnancy, but was positive that I had not even been pregnant. Now I’m confused as to what happened and why I would get several positive tests but not be pregnant. Someone give me insight please 😭.