hurtin'&workin'

I am currently at 80% disability for depression, kidney disease and chronic back pain. I have been at 80% since my discharge in 2005. My dr at the VA told me on Wednesday the 30th of December that I will never have a pain free day for the rest of my life. He told me that I was a 'at-risk' for falling since I fell four times last year. I am supposed to be going this Wednesday, the 14th of Jan for a power mobility chair, (scooter). I am currently having to work due to finances but I want to see if I can qualify for unemployability but I don't know where to start....I know I gotta not be working for the first step.... I work each and every day in severe pain and spend the majority of my day crying in pain, I'm usually out of work about 6 days per month due to the fact that I can't get out of bed in the mornings. I've recently been diagnosed with overactive bladder which is a direct result from my kidney disease. I'm not sure when my next evaluation is for my disabilities and I'm not sure how to find that out. I know I can get 100% if I just knew where to start. Thanks in advance for any and all help!