On my feet the toes and top of the foot are red, and I mean RED! I do not know what is causing this. One of my doctors thought it was caused by a medicine - but that did not turn out to be correct. This has been like this for about a year. How do I wear sandals with my feet all red!
I'm not a doctor but here are some thoughts. Several things come to mind. One is that you have an allergy that can be caused by your laundry detergent, or your fabric softener or even your shower soap or shampoo. Residue can be left on and act as an irritant. When your feet get hot and sweaty, the allergy gets worse. The second is that you have some kind of fungus that is triggered by heat and moisture, the kind of conditions that occur when you get hot and sweaty and stay in shoes for long periods of time. The next is that there is a friction irritation from staying barefoot in shoes for extended periods of time. I get that when I go without socks and stay in shoes, but it usually resolves fairly quickly.
Did you get a red pair of shoes wet? red socks? Friction between nylons and tight shoes?
Go to another doctor-maybe a dermatologist.
Mine was caused by an egg allergy.