According to your description it seems like acne
to me,because the acne doesn't always involve the face but it can also involve back,sides of the arms and chest,especially if the acne is adult onset then more unusual sites are involved.
The other best thing to do would be to check your bloo sugar levels because recurrent boils
are common in Diabetes
So it's best to see your GP to see the lesion live and then if he thinks then he can do a blood test
for Diabetes and if suspect Acne then he can put you on oral anti biotics.
I hope that will help.
Thanks a lot and all the best.