My best friend recently found red spots on her soft pallets and she's worried about them but doesn't want to tell her mom.

See below: It's a good chance this is nothing of great significance. By the tone of the question it sounds as if maybe your friend was doing something she shouldn't have been doing. Red spots on the soft palate of your mouth could be from many many different reasons. Would suggest you shared it with her mom or some other responsible adult that can further evaluate this issue.