boyfriends phone

i have recently got a new iphone 15, which means the charger is different to any other. I haven’t had chance to get one for the car yet, me and my boyfriend are out cleaning the car and gone to a few shops and won’t be back untill later on. bummy phone was close to dying and i had told him, we went to the shop to buy a charger but it didn’t work and was dodgy, i then said it’s fine and ill go without untill we get home, i honestly didn’t mind and i’d rather use an apple charger anyways. he was fine with this, Untill i told him i can just use his phone for music while he cleans his car, this is when he changed his mind completely and got in the car and drove to the shop, i kept saying it’s honeslty fine don’t worry and he used the excuse off i’ll be bored. why is he so weird when it comes to his phone, other times when i go on it he acts all strange and asks for it back cuz he’s “ bored” after me being on it for 2 minutes. its odd and it upsets me i just want to know other people’s thoughts