Chest tightness/burning sensation

So, for about a month now, I’ve been getting this weird sensation of warmth in my chest every once in a while. Naturally, my mind went straight to cancer. I went in for an ultrasound and everything came back 😍, but they couldn't tell me why I'm feeling this heat. I deal with some breast tissue issues, but I've never felt anything like this before, so I really don't think it's related to that 🤷.
Does anyone have any idea what else could be causing this?😕

It is entirely possible that we are looking at some sort of hormonal imbalance here; furthermore, one cannot discount the significant impact that chronic stress or clinical depression can have on such physiological shifts.

I’ve had this sensation of warmth on the right side of my body, specifically just under my right breast, lasting all day. I wouldn't call it a burning sensation, but rather a distinct feeling of heat...
Could this be related to something else? Yesterday, I woke up with two red bumps on my elbow, almost like insect bites. Is it possible they are connected?

It’s honestly tough to say for sure, because it could just be a pinched nerve or some kind of nerve pressure, and it might not even have anything to do with those little lumps at all... I mean, without actually being able to see them myself, I’m just shooting in the dark here... 🤷

The bumps feel similar to a mosquito bite, though it’s possible that's all it is. I don't recall actually being bitten, and while I would have taken a photo, I can't get to one right now :/ The heat has died down a little bit, at least.