If you are thinking about filing for SSI and are not sure if what you have is considered Disablity .. Please go to their web site and look at the disablity listings,
if you have one of their (listed illnesses) on their site chances are you wont need a lawyer too get your claim approved.. Just make sure you follow what your doctor prescribes for you in the way of tests to prove what you have.
They can not argue with tests results.
Best of Luck
Ryushie