New to HIIT week 4-5 of pregnancy--safe??

L

Hi everyone, today I found out I'm pregnant (I am 4 weeks and 4 days) and after a few minutes of joy and disbelief of course I'm already freaking out about everything.

Like this: I'm 36, have a normal BMI (high normal, I am 5-8 and 158lb) and while I was a college athlete (water polo), I haven't been super active for the past decade. Like, I get into bouts of swimming, or hot yoga, etc., but it's not as consistent as it should be.

The past 8 months I haven't done much, until weeks 1 and 2 of this pregnancy when I took a few Jiu Jitsu classes per week till I realized it wasn't a good sport for someone TTC! So end of week 3, just a few days after ovulation, I started at an HIIT circuit training group workout place (maybe like Orange Theory but without the HRMs? And kind of Crossfit like but with less focus on heavy weights). So coming up on week 4, right around implantation I was doing 4 straight days of intense 50-minute workouts, where I pushed myself HARD. Took a few days off and then this past week, coming up on week 5 I was a little easier on myself. Partly because it was 100 degrees here in SoCal. But I still did 3 50-minute workouts, including HIIT sprint stuff.

Thing is, I was told by my OB that I might not be ovulating, or might have a uterine cyst, due to mid cycle bleeding and a few other irregularities, so after a few months TTC and stressing about it, I really just thought I would assume I wasnt pregnant and live my life (besides cutting out alcohol) and get healthy. But maybe I worked out too hard?

So 1)-- have I hurt the fetus? What could happen with overheating/getting too out of Breath, in the first 5 weeks? When would I know? And 2) what can I do at this place going forward? I've paid for a few months and they seem to be GREaT about individual modifications. And I know for my mental and physical health I need to keep doing something. Specifics are welcome!

Please don't scare me too much, I am a very anxious person which is partly why I've started exercising, because it helps my mood so much. Thank you!! :)