I have a 9 month old yorkie. I trained him to sit and lay down. Hes is very stubborn.he is pad trained and when I'm not home he'll pee in the bathroom shower or right next to his pad and not on it. Also leaves a big mess with anything he can find in the house. How can I stop this?

He needs to be housebroken and trained to go outside, not expected to use pads all the time. How big is he? Do you live in a city or rural area?

I suspect that he thinks he's peeing on the pad. Put it in a shallow box so that he knows where the edges of it are.
Or if your shower has no tub, which I suspect, put the pad in the shower.

As for messing up the house, he is bored and under appreciated. You need to spend more time with the poor pup!
I'll bet your hours out of the house are long, with commuting. No pup should be alone this much.
Scrape some pennies together for doggie day care.