Sitting all day, it's the new american sickness.
Our bodies were simply not meant to sit. Unfortunately for those of us that have to, that usually means that over time, we will develop pain.
You can see an osteopathic doctor (do) who practices omt, or a chiropractor who can do hip manipulation.
In addition, muscle relaxers from your doc may help. Heat, stretching, getting up will help. G'luck!