I was quite self-conscious the first time I wore a mask out in public on one of my weekly runs to the post office. When I first got there, I was the only one wearing one. I passed a former student of mine going in, and I could tell that he not only recognized me, but made a judgement call along the lines of "Of course, HE would be wearing a mask when out." Meanwhile, my glasses were fogging and the smell of my breath was already bothering me.
Only as I was headed out did I see someone else come in also wearing a mask. Our eyes met, and I think I saw the same relief I was feeling of not being the only one in her eyes as well, but I could have been imagining it. I got back to the car, took the uncomfortable thing off and felt both relief from breathing in the fresh air and shame that I was so affected by the mask for such a short period of time while there are people wearing masks for their entire workday.
It's become easier for me since then. I've felt both more comfortable and less self-conscious Sure, I still have the suppressed desire to say to those without masks, "I'm not wearing this for me; I'm wearing it for you," but I'm pretty sure that could get misinterpreted. Besides, superheroes shouldn't have to explain why they wear their masks; they just need to keep trying to save lives.