Medical - Heat Illness

Hi guys a question , I was on an insertion tab in the army and it was about 20 plus degrees had a gpmg , 750 link and fainted , the doctors put it down as a heat injury on my medical record and I saw on the jsp 950 that you are graded p8 if this has happened to you. However , it still says I can appeal this . How likely is it going to be that I maybe rejected for a one time heat injury I had.