I have a small pimple-like bump on the skin of my stomach. It has been there for about 1.5 years. The surface is rough with a slight pattern. When touched, it gives a pricking or sharp sensation. This sensation increases when the weather is hot or when clothes rub against it. There is no pain, bleeding, or discharge. It hasn’t grown or spread, but it hasn’t gone away either. I would like to know what it could be — possibly a wart or some other skin condition — and whether it needs treatment or removal?