Anyone have multiple beta levels done? Doubled at first now much slower

[Pixie2320]

I started out perfectly doubling and then some, but the last few have not any actual experience with not doubling after 1200 and have a successful pregnancy? I'm high risk because of previous losses hence the number of draws, I'm also on progesterone supplements as that's what caused my previous losses

3/7- 60
3/9 - 151
3/11 - 304
3/14 -756
3/16 - 1280
3/18 - 1,824
3/19 - 2,106

I should be 5 w3d based off my ovulation date