Although this could be related to anxiety, it honestly sounds like something else is going on. A common cause of this kind of breathlessness is iron deficiency, so if you feel like you have other symptoms of that I would def talk to your doctor!

I agree with goblin49. Years ago I thought it was my weight or stress/anxiety or I was just out of shape. I didn't see a Dr for almost a year. It got worse. It was happening not only on stairs, but walking across campus for classes. Turns out I have anemia (iron deficiency) and asthma.

I get that with anxiety like going up the steps to a doctor appointment or something like that I’m totally out of breath at the top sometimes from it. But don’t get that way going up the stairs at home