Halp! How can I be less nervous during phys ed?

So I have phys ed this year, and I can't stand it. It's not because I'm physically incapable of doing the stuff, but it's because of my anxiety. I can't even walk in the gym without breaking down. I feel like everyone is staring at me when Ido stuff, and I have a panic attack almost ever time I walk out of the gym. How can I get over this, and make myself relax and enjoy it?