Hey Gray Gato -
I don't know about you, but getting nervous before a trip is normal for me. I wish I knew how to stop that feeling, but I haven't managed to find the magic potion yet. All I know is that as soon as I'm on the road (driving or flying to my tour), I'm fine!

I just got back from an almost 2-week tour in Nova Scotia, and I had that feeling before I left. In case it can help make you feel better, here's the blog entry I posted just before I left:
Last minute nerves

Or - maybe I should call them "last day nerves"...

Yesterday was packing day for my upcoming trip, and tomorrow is my departure day. Today, and last night? My very nervous day! Honestly, I have no idea why I get an attack of nervousness right before I take off on a vacation. It's not like I haven't used my bike as my primary mode of transportation for a vacation. And it's not like traveling solo is something that is new to me. In fact, I love traveling on my own and on my bike.

So, crazy nervousness, be gone!
On the altitude front, well, it might make you ride slower, or... But you'll be fine. Keep drinking lots of water as others have already advised.

Have a great trip!
--- Denise