My girlfriend has stomach pains and she to pee every 15 min and also so her breast feel heavy ans brings pain?

Abdominal pains. It could be many things, but you need to make sure there is not a bladder infection (a urine culture) or pregnancy (blood or urine pregnancy test). If its not either of those, further workup will be needed. If it gets very severe, go to your local er or talk to your primary doctor.