First off, kudos to you for being a nurse and being there for your patients during third shift. It sounds like you have been taking the right steps to get used to a new schedule. A new sleep schedule is tough on anyone- I don't think there's anything wrong with giving your friends a heads-up about the schedule change.

Based on the information you provided, it's too early to tell. Even a non bi-polar person would most likely need about a good 2-3 weeks to get adjusted to a 3rd shift schedule.

Keep us posted on how you're doing