I actually developed folliculitis on my buttocks...I was completely weirded out about it ( and of course, very annoyed). The doctor checked it out and thought that since I had recently stopped taking antibiotics ( for surgery) I might be more prone to developing infections. So, it's not even a big deal...It's very common.
Anyway, you should go to your dermatologist and they can prescribe a cream or antibiotic, depending on your condition. You mentioned that the cream doesn't help much...Maybe you need a stronger one or even an oral antibiotic. Hope it helps...
As for me, the pimples have subsided but I do occasionally get tiny ones again. I will definately see a dermatologist about it too.