Anatomical Confusion

Is it normal to have a decent sized lump that covers the entrance of your you-know-what kind of like a door? It also seems to be connected to my urethra or just very very very close to it. It doesn't hurt it's just kind of there and I honestly don't know what it is. I've had it as long as I can remember and my mother has been telling me it's normal, but I'm still curious as to what this thing is.