I Have Developed, Blister Like Sores Under My Breasts, Between

I have developed, blister like sores under my breasts, between my legs & around the outside of my vagina. I was thinking this is from the heat wave. But I am concerned. I will be seeing a physician in 1 week, but concerned that I should get in sooner. Because it’s everyday and not improving with all the hygiene care I am taking.
Do you know what this could be?? I have been married for 21 years so no new sex partners and to be frank husband & I have not had sex in past several weeks because of these sores??