Well the first time I got on a horse, it was really scary too. I think your body gets used to the feeling after a while though, and then it starts to feel natural. Although my legs are still always sore the day after I horseback ride, it's really worth it.
I'm glad you enjoyed the summer. I actually took a pretty intensive summer course for part of the time so it kind of cut out a portion of that relaxation for me, but that's alright because I still enjoyed the summer as well.
Anyway, think of it as the start of a new chapter; I'm sure you'll do fine ALIT. The intensity begins next week for me as well, it's just that time of year again. Good luck!