Lake Mendota, bikes and boats

I’m sure that sport psychologists / physiologists have a name and maybe a reason for these feelings…
I’m getting ready to ride the Door County Century this weekend. This means that I have spent the last couple of months riding longer rides and building up time in the saddle. I was up to about 190 to 200 miles a week two weeks ago. I was also working out with a personal trainer twice a week. In short, I was getting a lot of exercise – 15 plus hours a week.
As this weekend approached and the up-coming century ride, I started to taper off my workouts. I dropped my twice-a-week personal trainer moving down to once a week last week and none-a-week this week. I’ve backed off the miles that I bike each week.
I’ve noticed that, as I taper back on my workouts, I get twitchy and anxious feeling but it is mixed with fuzziness and sleepiness. I’m also kinda grumpy which (I think) is unusual for me. It is an unwholesome combination of lack of mental focus mixed with an over-caffeinated kind of buzz and a lethargic desire to nap for hours on end. I’m a bit concerned about the end of the biking season which coming up soon due to lack of light, too much cold and then snow. I’ll need to ski a lot this Winter and find another indoor endurance exercise (swimming?) for those long Winter months.
On the other hand, the rest has felt good. My shoulders, neck and hamstrings were starting to complain about all the work they were doing. But then again, all this exercise has meant that I could eat well and still drop weight.