can not find federal Doctor in my area

I have a ptsd claim. I went to my primary MD on the first day, however, she does no do federal comp. I have been unable to find a psych Dr. in my area with in 100 miles. I have an excuse to be out of work that states. off work until evaluated by qualified provider at least 3/25/2013 written by nurse manager of employee health signed by nurse practioner. It is 3/27 and have not returned to work. Still having quite alot of difficulty. What am I to do to get treatment, My work is questioning my excuse which was written at work from employee health. I have been told that I can not pay a MD out of my pocket for this workers claim. I don't feel I should return to work when I am feeling so horrible.