Stomach pain at 30 weeks?

I have noticed that I have pains on my stomach and it hurts when the baby is sideways.. It seems like she's popping out of my sides of my stomach and it's really painfull.. I cannoth sleep on my left or right side because my stomach gets really sore.. Is that normal? Or should I go to the ER... Or should I wait till Friday when I have my ultrasound appt...