Ladies I need help!

I had a missed miscarriage feb 20. I got my first period March 21. Was expecting my second period April 18th but it has not come. I’ve taken 5 pregnancy tests and they are all negative.

My question is this: is it possible that I am pregnant and that because I miscarried at 12 weeks I still have high hcg levels? Too high for the test which is causing a false negative?

I’ve written my dr but have yet to hear back. Wondering if anyone else has been in this situation or what some opinions might be about what’s happening?

Side not: I did have sex several times while ovulating. I know that doesn’t guarantee anything