Sometimes things seem uncomfortable when you first try them. Have you tried leaving them on for an extended period of time so your body can try and get used to them? I'm not really an expert with tiger paws or wrist grips, but maybe the ones your friend lent you were already adjusted to fit her wrist, thus feeling uncomfortable with yours. I'm pretty sure some body accessories like those need some time to get used to, so if your instructor really needs you to wear them, why don't you talk to your parents and maybe go talk to a specialist at a store? Who knows, maybe there's alternatives? Good luck!
