Levels dropping - HELP

On Monday I was exactly 4 weeks, I got blood work done and they said my progesterone was at 17 and they thought that was a little low so they put me on 200mg a day and wanted me to come back Friday to check and make sure all of my levels were rising.

They called me Friday night and said my levels were not rising and that I would miscarry over the weekend.. :( I have no spotting, no cramps.

I’m preparing myself but still hopeful. I’ll be 5 weeks in 1 day.

So my question is... has anybody else gone through something like this and still had a healthy pregnancy?