Sorry I meant is it only painful when you externally rotate to 90deg in 90deg shoulder flexion or only in 90deg abduction. Not sure whether you were a health professional or not so tried to keep it simple.

Does isometrically contracting into internal rotation at the limit of your external range increase or decrease the pain? Any pain on internal rotation isometric test? Is it tender inferior to or on the coracoid process or over bicipital groove?