My friend is worried, 2-3 months she has been having 2 day periods and her breasts still hurt after last one. isn't on birth control? possibly preg?

Probably not: If she is having a period every month then she is probably not pregnant. Breast tenderness is common and can be due to excess caffeine intake (coffee, tea, soda, chocolate, energy drinks). She should check a home pregnancy test to be sure and if she doesn't want to become pregnant, using condoms or seeing her doctor about getting on birth control is a good idea.