Bad Rotator cuff Pain

Recently starting on date of 8-31-2010 I started experiencing horrible rotator cuff pain in my left shoulder. I went to the ER on the 1st of September because I could not take the pain at that point. It was a constant pain that would not ease up. I have had a history of discomfort in that shoulder for a while but It came and went. This is the 1st time I have ever had the pain so bad that I went to a medical professional. The X Rays came back looking fine and I was sent to a Orthopedic. I was diagnosed with tendinitis and given Voltaren-XR and Percocet. For the 1st 2 days the pain got better and at one point on the 4th day I forgot I was hurt. The next day I felt some discomfort but went away after a walk. I decided to ride my mountain bike for some cardio. I noticed some pain but not to much just discomfort. That night the pain was horrible again and was out of Percocet. I then called the Orthopedic and told him I needed some more pain medication to be able to sleep at night. I was also told to get a MRI but I am unable to do so due to lack of money right now.

My question is should I completely rest my shoulder and not use it?
And is tendinitis suppose to hurt so bad like this?

[iris986]

Your Vitamin D is low, take 1000 IU a day and in 2 weeks the pain should be gone. Several of my friends have taken my advice  and their pain went away.

[Tyler007]

Thank you for the reply back I will try the 1000 IU starting tomorrow and see how that works out.