Wtf!!!?

So basically today I was walking to get my pe kit at school and I saw some of my close friends (3) and one of them-call her A- asked me if she could borrow my trainers and I said” I don’t think they’ll fit u “and she’s already been to my classroom gone through my stuff and tried them on because my other friend - B- gave her permission! And I didn’t wanna be rude so I was like “oh ok sure” but they then sent me to my tutor to get this kit and bring to them and I know I’m probably overreacting but this isn’t the first time that B has done something like that. I asked her to do my sc streaks and she went round and showed everyone who I had blocked and she’s barely spoken to me since school started and she thinks she can just give permission? Idk if I should ignore it and not cause any beef or say something about her ignoring me bc it’s just ughhhhh....!!!!!!