Puppy with zit like bumps around ball sack?

I have a 4 month old pit/boxer. As he was sleeping i noticed he had redness around his ball sack area (he sleeps in strange positions). I looked more into it and noticed he had bumps only on the right side of his ball sack. The pumps look like zits. He has 4 or 5. I noticed lately he was licking down there a lot more and nibbling down there but didnt really look into it until now...... what could it be?