Lump on my yellow lab

Question
I recently noticed a lump on my 4 and half month old puppy. I'm actually not sure if it his testicle that has just descended or not. It is up towards the top of his penis on the side. It is firm to the touch and kind of a glossy looking. I'm not sure if it is anything to worry about or not. Any info is great.

Answer
It's hard to know exactly what it is your boy has.  Your boy should have his testicles already and they should be in the back in the scrotum....preferably there should be two distinct testicles.   

When puppy boys wake up or get excited, they will have erections, and you will see the bulbus glandis through the skin, which looks like two huge knots an inch or so in towards the belly from the testicles.  This knot will go away when the pup's excitement goes down.

If it is not the testicles or the bulbus glandis, and the lump is there continually, I would take the pup in to the vet as a knot or lesion on the skin could be something serious.