Help! I’m scared!

So I miscarried in January of this year so I’m terrified.

We found out we were expecting on 11/28 after our second IUI was done on 11/16. I’m 4w+6 today.

I had HCG drawn 12/1 and it was 267

I had HCG drawn yesterday and it was only 659.

I’m worried that’s it going up slow. I’ve had light nausea and breast tenderness and EXTREMELY sensitive sense of smell. I have had some light cramping; however, on Monday I had sever cramping for 3ish minutes. (Like doubled over in pain). I’m getting HCG rechecked in the morning.... they weren’t happy with where it was at yesterday. I’m scared I may be losing this angel rainbow 🌈 (I have no living children).

I’ve had no bleeding and hardly any cramping since Monday..... thoughts?😢😢😢