Okay so i am a 15 year old male(almost 16) and over the past year or two ive had mild chest and back acne, but nothing to stop me from going to the beach and such. But last week on a vacation my mom noticed a bunch of bumps on the bottom of my back which is clearly acne. I just got it all of a sudden and it appears to be getting worse..any ways to get rid of this? or how long it lasts?