I get anxiety every time I like someone?

It literally effects my social life and I start thinking I'll never be able to like someone because I get panic attacks whenever I'm around that person and it ends up ruining the friend ship. I've changed my sexuality because of this, I am bisexual but for awhile now I've been calling my self asexual because I don't want to be with someone and have a relationship with them because of this anxiety. I've tried to calm my self down but every time I'm near them, think about them, or talk about them my heart starts racing (not in a good way) I get nausea, and feel like I have to go to the bathroom every minute. Please help me, I know theres the meditation and stuff like that, and theirs medication but I have no clue how I would tell my parents about it, I've tried hinting about it but I don't know what they think about it. Anxiety does run in the family also... I'm 17 if that matters at all :/