Hi, I'm Emmanuel, 40years. Few Weeks Earlier, My Son 2,

Hi, I'm Emmanuel, 40years. Few weeks earlier, my son 2, rested squarely on me beside my penis with his knee and I felt some pain at that very moment. But while I observed myself yesterday, I noticed that there is swelling on the left side of my penis. When I feel it with a finger, I notice a kind of lump inside. Please, what do I do? I'm already afraid. I don't know what this swelling is.