My rabbit just peed all over me and I chased her around with a tube and hit the ground right next to her and scolded her.
What would be a better way to tell my rabbit not to do that again (if there is a better way)?
Chasing a rabbit is not a good training technique, it just causes fear responses. Loud noises, thumping the ground and a stern voice are all good training techniques.
Rabbits occasionally pee on people when they are snuggling in your lap. It does not happen often but does happen. I don't think anyone has a good explanation for it, some say that means they love you. But it could just as well be like a child wetting the bed, comfy warm and dreaming they are in the right place for the job. I handle a lot of rabbits and probably get peed on once a year like this.
If your rabbit has a full bladder and you put to much pressure on the bladder it will empty, I have caused this to happen when handling a rabbit for too long without giving them a potty break.
There are several other reasons, that apply to any animal, fear, anger, territory issues. But those are seldom the issues with a pet rabbit that is well handled and use to their person.
For the most part, rabbits prefer to urinate in specific area (litter box). Other than ensuring that their place to pee has a litter box, little urine training is actually needed.
Side Note: If you have been handling strange rabbits, and come home with the strange rabbit smell, you or what ever you sit on may get marked, to clear away the scent of the competitor. When I have been at the shelter handling lot of other rabbits I always change clothes before sitting down, or interacting with our rabbits.