Billy needs a friend

Billy has a lot of energy and some times he goes a little crazy playing inside the house and jumps every where I read this was a normal behavior for dogs who live inside, even if I take him out at night he will do this every morning and before going to bed.

I though that playing with Aki will be enough, but Aki is a cat and he wants his sleeping and "feline don't mess with me time."

I was thinking of getting a second dog, but later I though that this could be difficult for both Billy and me, we had to go to training the new dog and getting it to get used to living with a cat and sharing space with Billy.

Should I really get another puppy?