Neutered Dog Bleeding from Penis

Question
My dog is a 2 1/2yr old neutered pit bull and I noticed recently that my dog has been having drops of blood coming from his penis not constantly but throughout the day & it's btwn 2 - 4 drops each time. When I first noted the problem it was an orangish color & I immediately consulted with our vet she said is was a bladder infection & recommended some medicine for him. Since completing the treatments it  stopped for a day & when it started hapenning again it is now a dark red color. He is still eating, sleeping, playing,etc. all the same. I'm not sure what else is could be. The vet said she was going to look into it & let me know. I'm just trying to do my own research in order to help him. Any ideas or recommendations would be much appreciated & welcomed.  

Answer
This dog needs to have a very thorough exam of the sheath area. This has to be done under sedation. There are many safe and fast drugs to do that.

Without a physical exam there is no way of knowing whether or not this is an internal issue or an external one involving the sheath.

Believe me, there are plenty of things that can get up inside there and cause infections/bleeding, etc.

Giving the antibiotics stopped whatever was causing the bleeding/infection, but that again doesn't mean it was internal.

Get him checked out physically. Thank you for neutering him by the way!!
You are a great pet owner.