I was masterbating and when I had an orgasm I started peeing, is that normal?
If you are young, it is very possible that what happened was squirting, not peeing. Female orgasmic incontinence (actually peeing during orgasm) is well known, but usually happens to older women who have had several children through vaginal delivery. Squirting is a different phenomena that involves several glands in the area that can be induced to squirt due to the contractions that happen. It is a rare talent. Congratulations.
Well,you just let go and your muscles relaxed during the orgasm,and thats okay.