I'm really confused I think

Okay...
Theres this girl in my class and she just turned lesbian or bisexual not to long ago and I know for sure that Im not gay but since that happened I've been having a funny feeling in my stomach that I could turn gay any minute and I dont know what to do about it. I cant go to anyone because Im scared of judgement...so can someone help me and Im 13...Im really confused so can someone please help me

First of all, people dont turn bi or gay, they either are or they're not...
And it isnt exactly contagious... unless you like people of the same sex you're not gay/bi

dont worry about 'turning' bi or gay. that is a choice, it doesnt just happen out of nowhere. you chooose to be one of those.