Is OTHER wrong in the post ? POST : I have been having a lot of lectures to catch up on which I of course need my calculator to study with. 
My brother has this test that he needs a calculator for . He has one, his friend however lost his and doesnt have one. He came to me and asked for it saying he wants MY calculator to give to his friend. I told him I'm sorry buddy I'm using it atm. He kept telling me his test is way more important than whatever I'm using it with atm , how he will use it for only a bit and return it. However I'm way behind my study schedule and needed to use it plus it's not my problem his friend lost his calculator before hos important test. Ie keeps begging me to give the calculator to him. My father thinks I should give him the calculator too saying how I was just doing it to "annoy him" . My bro left  because he was running late with one calculator. My dad is now mad at me cause I didn't listen to him . So AITA?