I'm a generalist, and not particularly expert at anything. And I get scared of my job future too. It's hard.
There is so much about chasing a career that is stressful: not knowing your future, putting yourself up for comparison against others, the competitiveness, the impression that everyone wants to employ a UX unicorn, the feeling that you can't control anything, the long waits, the empty promises, the concept that 'if you simply do this course you'll win the job you want', the 'Facebook Effect' that life is rosy and successful for everyone else, the sense that if you're really going to succeed you can only rely on yourself... In the long haul of looking for a job these things feel like the harsh reality. But, although life can absolutely suck sometimes, I don't actually believe any of these things are the truth.
I like @maxflyer's fighter thing—viewing the whole thing as a quest for opportunity, with all the gruelling work and creating of our own luck that it entails, and without knowing if, in the end, we'll come home with the prize or not. Maybe we won't? But if we follow our noses we'll go forward to somewhere. Noticing and adapting to the opportunities we're presented is wiser than thinking we can control our destiny by doing the 'right' things.
From my own experience, I'd point you down the path of using a bunch of your skills in one (junior) UX role, rather than going for something specialist yet. There be dragons for the not-yet-experienced.
Give fear a punch from me too. Thanks for sharing how you feel!