Had my first in person studio lesson this week. Also from a low count state.
We wore masks, and extended hand hold. Just one student/teacher in the entire studio.
The mask was hard for me. It took 1 hour after the lesson for my breathing and heart rate to stabilize. I mean it's doable, but it's like exercising in high altitudes.
Another student said he tried both cloth and N95 for ballroom dance but N95 was much easier to breathe in since there's space in the mask. I can't find anywhere to buy N95 mask so far.
Sorry to hear you had trouble with the mask. What sort of mask were you wearing? Do you have any health conditions (asthma, heart disease, etc)? That sounds like a long recovery time.
A properly fitted N95 mask (with a good seal, so it's effective) should be much harder to breathe through than a cloth mask or disposable mask (the dust masks and others, some of which look like surgical masks). An improperly fitted N95 mask is no more effective, and may in fact be less effective than the other types of masks, since one would be breathing around it and not through it, and thus not getting the filtering built into the mask. And most recommendations are that people don't need N95 masks outside of high risk exposures, such as health care workers doing procedures on sick patients.
So - instead of looking for an N95, I'd suggest you try a few things:
Try a different type of mask, such as a cloth mask with fewer layers or made from lighter fabric. Perhaps a bandana would be more comfortable, as that is looser.
Try a different type of disposable mask if available, perhaps a different style will work better for you. I think the styles with space in front may be called duck bill or similar.
Adjust what you are working on at the studio to decrease the level of exertion so you're not getting winded during the lesson. Maybe rumba instead of jive, more breaks in between working on things, slower technique drills, etc. You can build up to more intensity in your dancing either over time as you adjust, or with breaks, etc.
Pay attention to your breathing during the lesson (or any other type of exercise) to make sure you are taking normal breaths despite the mask. Maybe you're taking shallower breaths, or less frequent breaths, or both due to the mask.
Also, try a bit of exercise at home (where no mask is needed) and see if you're having the same problem. Maybe you're just a bit out of shape from quarantine, or maybe you have a new health problem that needs attention (in other words, perhaps it isn't the mask causing the problem, exactly).
Maybe others have other ideas for you. Hopefully something will work for you to make the mask more comfortable to dance in.