Kendalle..if your piggie was jumping all around and squeaking while you were itching him & then he peed all over you then that sounds like he was irritated with they way he was being pet.
They can get moody like us and they will sometimes jump around and squeak at you to stop and then pee out of frustration. Be careful cuz sometimes they can turn around and nip at you too. They can be quick.
Dont feel bad , it takes time to learn what your piggie is trying to tell you. Listen for teeth chattering...they also sometimes do that when they are upset. Its a warning that they are about to bite.
If that happens again just talk to im softly and take note of what you were doing at the time...you will learn what piggie is trying to tell you.
What are you using as bedding? If you need to change it and dont have any bedding like Carefresh use newspaper for now and even bunched up paper towels. Piggies are expensive to keep because they do need to have their bedding changed like once a week perhaps more for those who have more than one piggie. If you dont keep the cage clean they can become unhealthy and not be happy and not want to eat.