Getting the jitters before a ride starts, that's a perfectly normal part of the ride. You're supposed to get excited. Enjoy it-- and then enjoy the ride.
More nervous that I have everything right though I have been over the itinerary 20 times.
My big concern is Eugene. I do have a Warmshowers host that has agreed to allow me to stay and actually a second backup host (thought I have not heard back from him on confirmation) so I should be good. But if one of those two people does not come through, I might be screwed. There is a Grateful Dead concert in town and everything is booked up.