pelvic/pubic bone pain

Hi I'm 16 weeks pregnant and I've been experiencing pain on my pelvic bone.. it feels like a bruise and it's worse when I'm switching sleeping positions... I'm a first time mommy so everything is very new. Doesn't feel like round ligament because it's only on the front of my pubic bone.. the nurse suggested I take Tylenol but it's not that kind of pain... and I don't like taking pain killers.