Working outside your comfort zone
Background: About a year ago, the director of my department quit to become a consultant, leaving us with three people. He wasn't replaced, due to budgetary concerns.
One of those people, the former director's secretary, drove me batty with her lousy work ethic. She would take assignments from me, and then when I checked up on her progress, I would find that they never got done, and I would often have to do the work myself, to guarantee it got done. When she was laid off, I was both disappointed and happy, since people now accurately gauge how much time I have in a day to work on their projects.
So, our department is down to two people. I take care of database entry, database reporting, deposits, and a myriad of other more technical job duties. Additionally, I am one of two people with IT experience at my company, so I've also been asked by the executive director to take care of some pending IT requests that need to be looked into.
My boss takes care of event planning, newsletter writing, donor relations (including most phone calls and personal contact), and attends meetings to represent our office. We work really well together, and I couldn't ask for a better boss.
Now: My boss is on vacation, for two weeks, leaving me in the office alone. This is a really slow time of year, and things should have gone smoothly. And they did, for the first few days. Last Friday, though, a lot of extra requests came in from the financial office that I couldn't ignore or put off, so I had to set aside my daily tasks, as well as the extra projects I'm currently working on.
Now, I've got a desk full of clutter and I'm behind on my primary job duties, I estimate, by three full days.
What's my point? I feel good about having taken on these unexpected duties, and handling them calmly. But I feel really lousy about being behind on my primary job, even though I'm confident that my boss would have prioritized my time the same way I did. And I'm really displeased with the mess on my desk.
Do you feel like it's good to stretch your mind, sometimes, and work "outside your comfort zone?" Even if by the end of the time, you're more than a little stressed, is it good for you to practice your ability to cope with things you're uncomfortable doing? Or is it better to work within the limits you're comfortable with, so you can be the most efficient worker you can?

Extending Oneself
I think that it is absolutely essential to move outside of your comfort zone.
Firstly, in today's commercial environment, where the "jobs for life era" has disappeared, you will almost certainly have to assume new tasks and adapt to new working practices and demands.
By taking them on under your own terms you will feel much less anxious and more able to cope. I think that the key is to ensure that you work out your own strategy for effectively dealing with it: keeping a tidy, organised and arranged desk so that you can find things when you need them could be a good start?
I think that the other thing that is relevant here is the subject of change. Change more than comfort zones is even more prevalent today and is something that a person with Asperger syndrome really does need to accept and come to terms with.
Again, if one can do this under ones' own terms and requirements, it can all become much, much easier.