Being permanently disabled does not affect your federal tax return, so the federal section of TurboTax will not ask about it. Some states might take your disability into consideration on the state tax return. If your state is one of the ones where it makes a difference, the state interview will ask about it.
Being permanently and totally disabled could affect whether someone else can claim you as a dependent, but many other factors are involved as well. In the Personal Info section of TurboTax it asks whether anyone can claim you as a dependent. If that is a possible consideration, you should check the definition of total and permanent disability, and the complete rules for whether someone can be claimed as a dependent.
There is a federal credit for the elderly or disabled (you don't have to be both). But because it has not been adjusted for inflation since 1983, very very few people qualify. If you qualify, TurboTax (TT) will automatically calculate it. I goes on Schedule 3, line 54. Box c should be checked and “Sch R” placed on the line next to that box. It is not a refundable credit. That is, you must have a tax liability to offset to get the credit. Very few people, with that little income have an actual tax to offset.
Having any social security income at all works against you. Essentially your potential credit is reduced by any tax you "shoulda paid” on the untaxed Social security income. If you have more than $5000 social security ($7500 Married Filing Jointly and both are elderly or disabled) or VA benefits you will not qualify for the credit.
If you think you qualify, and TT missed it, In TurboTax (TT), enter at:
Federal Taxes Tab
Deductions & Credits
-Scroll down to:
--Other deductions & Credits
-Elderly or Disabled credit
See schedule R for detailed calculations. http://www.irs.gov/pub/irs-pdf/f1040sr.pdf
http://www.irs.gov/publications/p524/ar02.html#en_US_2014_publink100038693