Do you only get out of SSI what you put it?

I don't think so. But it's a great question. It has me thinking. My FIL lost his limbs over 40 years ago, and he continues to get the same amount of SSI. Nothing has changed. I can't imagine that he has paid in much, seeing as how young he was during the time of injury.

No, some get more and some get less- depends on how long you paid in-how long you receive and how much you paid in-
Although since it was military don't they have something for you in terms of disability- my guess is if you were denied benefits through the military- you may be denied through SSI- either way- an attorney with experience is your best bet as I have heard the SSI is difficult to navigate-

IDK. My son received SSI in Hawaii, he was a toddler at the time, never paid into it. So, IDK about you getting only what you paid into it. Your best bet is to apply, and see.
Now, in Texas, he would get it for a year, then we'd get a letter saying he never qualified, and if he could afford it, he had to pay it back. how the hell they though he, at about 6yrs old could pay it back, IDK. They also considered my hubby's TDY pay as our income. I tried explaining what it was, and that we, as a family, never got any of it. But, they included it as income. After 2 years of him getting it, then that damn letter, I stopped applying.
Just call the local office and ask. And, are you getting disability through VA?