the kind of pain you are describing is not labor. the contraction/labor pain comes after every few min and stays for a moments and has its pattern ,that you will know right away once it starts, labor pains never go away with changing positions or sitting and standing.
i hope you get this answer while you stilll need it, the kind of pain you are describing is a pelvic pain associated with disalignment of the pelvic area and possible malposition of the baby, if you have this pain a chiropractic treatment will help you , please go through this website to find more about this condition;
http://www.plus-size-pregnancy.org/pubicpain.htm#Anatomy and Structure