Suggest Remedy For Blood Filled Bumps In Groin,armpits,inner Thigh And Back

I Have really bad spots that are filled with blood, in the groin and under the armpits, also inner thighs and now one on my back, Doctor gave me antibiotics that didnt do anything now on a months supply of antibiotic minocycline 100 mg. I am 53. Doctor said its a form of acne???? Had diabetes test and cholestorol tests they are all fine. Puzzled as its getting worse