Absolutely. Somedays, the 'mojo' just isn't there. All of the previous comments here are spot on, in terms of what I've experienced at one time or another. For me, the biggest factors are fatigue (physically or mentally), and not eating well. I've really noticed, when my eating habits degrade, it affects my ability to think clearly, my hands become unsteady, and my ever-aging eyes have trouble seeing the important details that are critical to the task.
I've learned that part of the 'Zen' of sharpening, for me, is to just not worry if today's not the day for it. Consistent with my user handle here, I tend to 'obsess' about the process for days at a time, and at some point, I can just feel that the time is right. That's when I'll pick up a knife and have at it. That approach has worked consistently well for me so far.
Don't worry about losing your touch. It's still there, maybe just resting up a bit. You'll get it back.