Hard lump?

In the shower today I inserted my fingers into myself and felt a hard lump. It is NOT my cervix. I can feel that too and I know what that is. I've never felt this lump before. It's close to the opening, as I barely have to put my finger into feel it. When I pressed on it, it felt like it was pressing against my rectum and gave me the feeling that I had to go, even though I didn't really have to.

Does anyone know what this could be?