No his bananna does not show it's self, his true bananna stayes inside the peel, but the bananna swells up 3 or so times it's normal size

His little doggie weener becomes....um....well, lets just say alot bigger then normal He gets so excited that he gets a doggie erection. This happens when I leave him in the house for an extended period of time (while at work, out to dinner or movies, grocery shopping) and when he greets me he always goes belly up so I can see what excitement had done to him

Is this a normal thing? It's a little embarrassing sometimes when I walk in the house with a guest because the guest usually asks "what's wrong with his "thingie?" How do I explain that my dogs gets a doggie erection when I come home? A little humilating but he's a boy dog and hopefully it's not all that uncommon!