Hello, recently when I was masturbating I notice a little bit of discomfort on my penis as I was masturbating. I checked my penis and saw no scar or cut on my penis so I continued and after I finished I looked again and saw three blisters on my shaft right before the head of the penis, two really tiny ones and one a little bigger. Right now it was formed into one big blister. I am guilty of masturbatin at least once a day and I never use any kind of lubricant. Could this be from the friction burn?

P.s. I have had a blister before on the same spot before. That I believe is from friction burn as well