Why do i sometimes get gay impulses? Am i gay?

I am in highschool and am straight. But, i never kissed anyone or had a girlfriend before. I have been rejected like 30-something times. I am just first giving some background info. in case it is needed for this question. But, sometimes i get small periods of gay impulses. I know a friends who are guys and we are cool. But sometimes it happens where i get a guy-crush on them out of nowhere and it the feeling lasts only for a couple days. I never want to do anything sexual with them, but i just feel like kissing/making out with them, holding hands with them, hugging, and just being close to them. This feeling only lasts for a couple days and after that i go back to feeling straight again. Only once or twice in my life have i ever felt sexually excited thinking about a guy. But i am straight and not gay. But, what are these gay impulses? Am i gay? Thanks!:)