Underarm rash/blisters

hello.

I'm 27, and about 80lbs overweight male.
2 days ago i ran out of antiperspirant and went over a day and night without wearing any.
Now i have developed overnight, darkish red blisters/rash under my left underarm.
they do not itch, but do hurt about on par with a sunburn but only when touched.
i shower every morning. I did develop an allergy early this year to the Degree brand deodorant i was using, and switched to Dove Sensitive Skin, which is fragrance free. That solved the allergy. this does not seem like that, but i do obviously have sensitive skin. I think it could be just from the added friction of not wearing deodorant. i don't sweat much, just damp really but it does feel noticeably more friction if i skip deodorant. i dont have health coverage right now so i can't afford a Dr. visit.

I washed with soap and warm water. then applied a little hydrogen peroxide to disinfect. i used some Hibicleans i had left over from an staph infection earlier this year; it's an antimicrobial wash. Then applied some neosporin cream. i also have the neosporin ointment. just shooting in the dark here though. not sure what the best treatment is.

how should i treat the blisters? does it seam like simple friction problem? should i resume wearing deoderant or maybe try baby powder?

Thank you.

-jeremiah