My daughter went against my will and used tampons?!?

My 14 year old daugter got her period 3 months ago.She didnt tell me about it,i found out on my own.Well in the store she went to but tampons and i said no.That's not for you.It will hurt you and it is bad for you.She got pads but then today i found a used tampon in the trash! I was furious! What a little brat! There not for her.I am the parent she is the kid and she must listen to me.I want to take her to the gyno to get inspected.Should i? And what can i do about this? Ground her the whole summer? Take away he phone? I already took the tampons away.