You don't have to be completely unable to work to be qualified for disability. I guess it depends on the laws in your country, but at least where I live disability is graded by percentage of remaining ability to work. To get 100% loss of ability, you have to basically be unable to move completely, Hawking level or something like that, even then it could be argued that he can work mental work, so you have to go through hoops to get 100% disability.
But the thing is that getting lower grade disability is increasingly easier.

Due to my mental problems (social withdrawal, loss of drive, so on) it is surprisingly difficult for me to work: any work involving a lot of new people is out, because I find it hard to communicate with people I do not know relatively well, then there is the more insidious symptom - loss of drive (how do you force yourself to work every day, when every single task you need to do, feels like a rock tied to your neck. I cultivate the few hobbies I have remaining, but even these sometimes feel like a chore, I actually haven't watched a movie in a few years because I just can't sit through a hour and a half of it.)
So due all that I am ranked as someone who lost 60% ability.
Depending on where you live the difficulty of getting disability may be greater or lesser. But it's not like you can lose anything. You will probably need to spend some time in the hospital to be properly diagnosed, but frankly I found it refreshing, at first it was hard, but soon you find out that there are all kinds of problems people have, many of them so much worse than what you even imagined possible. But then you realize that not a single one person in there has the same problem, all of them have unique situations including yourself. It is really fascinating actually, with physical injuries if you've seen a few broken bones, you've seen them all, with mental illness it's entirely different, even two people with same diagnosis may and will have different symptoms of different severity.