Help my python has blood blisters

[blackjay]

i noticed about two weeks ago that my baby ball python had a blister on his side at that time it was quite small and hardly noticeable i thought it would go away and that it was a heat blister so i turned the temp slightly down in his cage i use dark brown wood chips and there is some cardboard in his tank from when he was at my dads house. can i use iodine to treat him?