I dont want to take away the importance and toughness of cabin crew training but its all about organisation.
Dont let SGITG scare you, i came from a non study background and have done 2 ground schools, one with multiple aircraft types and one with a single type and i found them both fine. The trainers dont want you to fail, so listen, concentrate, pland your time right and you'll be fine. If you arent sleeping then you arent following a plan well enough.
You'll be fine - my suggestion is stop thinking now and just DO!
All the best
