I would call your doctor. It can be a number of things. You will want to get on to of it if its anything serious so it doesn't affect you through out your pregnancy. I don't think it could be anything to hurt the baby but will just cause you problems. don't stress on it. Your doctor will let you know what's best to do.
Sometimes when you move a little too fast or too much you will get those pains like a runners stitch. In your sides....if it was like that then it's more the fact that you strained your ligaments a little. I did that when trying to go for a walk through a trail my last pregnancy. I was walking all the time but one day it really hit me. I had to turn back around and walk back when I hardly even started!
It almost feels asthough I shifted my pelvis bones
Eeek! That could be many things and painful things shouldn't be taken lightly. check out this http://www.ucsfhealth.org/conditions/pelvic_pain/signs_and_symptoms.html
You should make a doctors appointment to stay on the safe side.
Oooh, that's a possibility. I have major problems with my pelvis and hips going out all the time in pregnancy. Visit the chiropractor if you can. I always go every few weeks in my last trimester. I totally need it!