You won't lose any experience if you've logged off or saved your character recently - experience loss tends to only be on the rollback after a crash, so use the save function if you've recently acquired some significant progress.
Your safe resting place can be reset by renting and resting in an inn room, which will set your faction base (if not in a player faction) to the Vistani nearest that safe resting area, either in Vallaki or the Mists.
