Help!!

15 weeks 5 days pregnant with horrible jabbing pains on the far left side of my hip. 
It's only at night, & sometimes it's a tightening painful jab that last 30 seconds. It's only when I switch positions. It's so painful! Sometimes it's almost throbbing after a jab.
 What is that? Is it something to worry about? I've had round ligament pain, but this just seems 10 times stronger.