Hi! Guess what? You are NOT crazy. You are not crazy. I promise you will not lose your mind or go any further than feeling scared with anxiety.
I have had the same for years and have a couple tricks up my sleeve that may help you. All of us anxiety sufferers have one thing in common and its that we have become hyper-aware of our bodies. Especially this flight or fight syndrome called anxiety. I don't know if you have notice this but when your not thinking about it your anxiety it will go away. I know, it's kind of like saying don't think about a white elephant. My anxiety got bad enough to where it was really affecting my living so I went to see my doctor. Have you talked to your Mom or Dad about this at all. If it does not be better you should tell them so they can get you an appointment with your regular doctor. He will know what to do, if he doesn't help you than tell your Mom that you want to see another. This isn't the end of the world, not even close, it just feels like that. There are also books that can help you with anxiety. Good luck to you, you can beat this with a little help.