Pimple in sensitive area?
It could be a lot of things, including an ingrown hair, a boil, or a pimple. Cyst is less likely, and tumor even less likely still. You definitely want to get it checked out, because it could be a skin infection. Skin infections (including MRSA) are most common in the nose, face area, armpits, and groin. I had similar symptoms but in my eye area when I had a staph infection in my skin.
I’m thinking, in order: ingrown hair, pimple, boil. Most of them are irritating, and the last one can get very unpleasant. (I know; I had a boil in my groin area that I was self-treating spontaneously release its contents, and I needed a doctor’s visit and two weeks of antibiotics to deal with the results.) I recommend a doctor’s visit, or at least a phone call to consult.