First off, where are you gav? In the states? And how old are you?
Getting a diagnosis does not automatically put you into Special Education classes. If you are 14 or older you have the legal right to sit in and negotiate any special interventions the school would like to make on your behalf. If you already do well in your classes, it is unlikely they will remove you from your regular classes. The goal is to make the educational environment as inclusive and non obtrusive as possible. That is the law.
If they are recommending that you seek a diagnosis, they are probably seeing certain challenges or struggles you may be having elsewhere - such as socially. They do offer classes and such for this and they can be planned into your day just like any other class. The goal of these interventions is to help you where you are struggling while providing the most 'normal' educational experience as possible.
If you are in the US, you or your parents can request, in writing, that the school do an evaluation. It involves some testing and some observation - you can even let them know you are very self conscious about it all and they will make accomodations to bring as little attention to you as possible.
I know it seems overwhelming.
Read as much as you can here. Read a few books. Learn all you can. Asperger's isn't some sort of dire, hopeless diagnosis. It simply identifies a difference in the way you approach the world and the interventions are designed to help you navigate the world a bit easier. It doesn't make you 'dumb' or 'ret*d' or any of those other lovely names people can come up with. In fact, many people with AS are extremely intelligent.
I wouldn't worry because it's nothing to worry about. ![Smile :)](./images/smilies/icon_smile.gif)