Any crossfit moms out there?

I've been crossfitting for 3 years and my doctor told me no, that if I want to exercise I can run on a treadmill so I'm switching doctors. I'm not high risk, ive had absolutely no problems with my pregnancy at all except for bleeding during sex around week 10 and I've had no bleeding or spotting since. 
I'm just so frustrated and my box owners want a note saying I'm on to wod, and I just feel like my new doctor won't even give me a note just because it's a liability issue. 
Thanks for listening!