are you sure its tendonitis? I thought that's what I had in shoulders but it turns out it was torn rotators in both and a possible torn labrum in left.
get an mri.
another member (bizmarkie) I have been posting in a thread on this board about our ART experiences. check it out if you can. if you're in nassau county I have a great guy. I've been to 4 sessions and its really helped.
My advise is to get an mri and do not start a cycle til you are totally pain free. If its tendonitis, a few weeks off can probably help. ART will help break up scar tissue and you may back in the gym before you know it.