If you don't get relief from all of the above options, you can try visiting a chiropractor or physical therapist. If that fails, consult with a pain medicine physician. The good ones are very skilled at diagnosing the source of the pain. I recommend finding someone who is board certified and be sure that they are an interventional practice which means they won't just ramp you up on pain medications, but will actually strive to find the cause of the pain and address it with non-surgical procedures.
You can usually check the credentials of any physician by going to your state's medical board web site (just Google the state name and Medical Board).
Hope you feel better soon - it is challenging going through the day in pain! Also I have been told by my doctor that it is perfectly safe to take up to 4 Advil every 6 hours if just two don't do the trick...