Principal told me not to appeal

It took 5 weeks & numerous phone calls to Principal before I got a decision on my short term disability claim. I was put on FMLA short term disability by my employer because of neck, shoulder, back & hip pain due to herniated discs, disc degenerative disease & nerve pain. I have been seeing a pain management doctor for 7 years because of the pain. I have been a receptionist for over 20 years where I am constantly sitting. Last year in november I was in a bad car accident. This exasperated the pain. I missed many days of work since for excriciating pain. I had been on all kinds of pills, had injections & physical therapy. Even with all of this proof Principal still denied my claim. They told me not to try to appeal because I would just be denied again. The people there are rude & condesending.