Getting over the stairs thing, the other thing that worries me slightly about living on the second floor is the lack of solid ground below me. Being on the ground floor significantly lowers the risk of falling through the floor, but with two floors of nothingness beneath me, I worry that the floor will give way and one day I'll wake up in the kitchen sink, 15ft below where I went to sleep. Irrational I know, but it's the little things in life.
It's no wonder that when I do encounter stairs, I struggle more than the average person; couple my lack of practice with the extreme dislike gravity took to me on the day I was born (or extreme attraction, if you will) and you will see that I never had a chance. I have a feeling I may become well acquainted with the sofa this year.