Pelvic/leg pain

I'm 30+1 and feeling great!!! For about a month now when I go to bed the inside of my legs hurt. Like an aching pain. It hurts right below my pelvis on the inside of my legs. (Like riding a horse for the first time in a long time) it hurts to roll over and sit up. Once I stand up and start walking it doesn't hurt anymore. Only when I lay down, anyone else having thus kind of pain?