What Causes Recurring Painful Bumps On The Pubic Area?

I have a recurring red bump on the front of my pubic area (nearing the right). I had initially assumed that the bumps were the result of ingrown hairs as I had shaved the hair in that area with a razor. However, I haven't used a razor recently, and I now am experiencing the bump again. It's relatively big for a bump (slightly larger than your average blister or spot), and very hard and painful to touch. It gets progressively worse, to the point where sitting down feels as if I am trying to squeeze or pop it. However, whenever I do get the bump, it disappears within a few days or a week or two. I am not sexually active at this time.