Starting school again this fall: How do I overcome my shyness and fear of embarrassing myself?

I know it’s stupid and counterproductive, but I’m hopelessly shy and withdrawn; I think I’m horrified of being seen av stupid, naïve and immature.

I have taken a HUGE step out of my happy-place, I’m starting school away from where I live in a month, and I’m getting quite stressed as to how I’ll cope with the new people and places, surrounded by intelligent and achieving scholars.

I’ve never had any anxiety-issues, no psyciatric worries at all, eccept being shy…
(And btw, I’m against medicating my every flaw, so no med’s.)