Still feeling a bit nervous, but hopefully that will iron itself out.
I looked at pictures of the types of planes I'll be flying on today, and the first one is a small one, just from Burbank to Phoenix, and the other one, from Phoenix to Chicago is a much bigger one (Airbus A320).
Just have my carry-on luggage, and a messenger bag, and feel like I have everything. Remembered my phone charger at the last minute last night. Decided that sneakers will be my one pair of shoes for the next 14 days, though I prefer slip-off shoes now that they make you take them off to check them.
Just breathe....just breathe... :)