I would go ahead and apply. It's not only for people that are seriously injured and are never expected to recover. As long as you can't engage in "gainful" or "substantial" work, you can be elegible for disability. It's also if your disability is expected to last one year or more.
You would have to prove what you've said with medical records and all, but you'll never know unless you try
Since I was born disabled (with a bone and joint disease), I was able to get SSD without needing work credits because I applied before I turned 22. Here's more info on that: [url]http://ssa.gov/dibplan/dacpage.shtml[/url] You might not qualify because you have been working and might be making too much money.
Here's how they determine if you're disabled: [url]http://ssa.gov/disability/step4and5.htm[/url]