Hello. Welcome to HCM
Cysts or boils
in the region of armpit are generally related to the sweat or apocrine glands which are abundant in the area. Being an area of abundant skin folds and also wetness due to sweat, wounds in the region heal slowly when compared to other body sites. so, your redness
can be explained.
presently it would not be advisable to use spray deodarants for some time, before wound repair is adequate. Instaed, you must keep the area dry by daily application of medicated talcum like neosprin or even mycoderm.
Hope this helps,