About yesterday my left testicle started being more sensitive to pressure, the way it feels after being hit, but I don't remember any serious injury. It was and still is only sensitive near the top. Then today, I felt a small lump at the top of the testicle, and felt the most severe pain when I pushed on it. It is a very small bump, almost like a pimple. The testicle isn't swollen or raised, the only symptom is this painful pimple-like bump.