The reason behind the recurring baltod ( folliculitis/furunculosis ) may be improper hygiene, excess sweating & diabetes. Considering your age diabetes is unlikely still my advice to you is that you must under go blood sugar level testing once. This is very much important ( as occasionaly diabetes may occur in young people) You should also receive proper antibiotic course such as Amoxicilline+ dicloxaciiline to cover both gram +ve & -Ve organisms. So it is advisable to have proper dermatological consultation. Improve your hygiene & get your BSL repors done which can help you relive from this problem permanently.