iPhone/iTunes problem, help!?

[biskitdog]

so my dad set his iPhone up on MY itunes that i was using previously using for my ipod nano. i went to set up my iPhones on this same itunes library but pressed "restore" instead of "new iphone" when it popped up (don't ask why, just wasn't thinking). and now everything from his phone is synced to my phone. settings, apple id, apps, everything. and all of my contacts were deleted. is there anyway i can reverse this?? i want MY iPhone back, not a copy of his.