Karen,
AN's are strange things, and everyone reacts differently to them. If you have a tumor (and hopefully your MRI will not come back as positive), it may not be large. It all depends on where it resides. As for waiting and making yourself sick...try to not panic...you really don't know anything yet. But, you are already getting yourself prepared in case you do have an AN...which is great news because that means that you are ready for the challenge.
As for getting through the shock...well everyone accepts it differently. I was positive I just had tinitus, even though I had researched AN's, I was just sure I couldn't have one. I was wrong. I spent the afternoon in shock, and then decided that I was NOT going to let this rule my life. I decided to research until I dropped...which I did. I looked in medical libraries (at hospitals), local libraries, the web, until I was positive that I found all the information that I could about AN's...the different types of treatments [watch and wait - surgery - and radiation], as well as the individual types of surgery and radiation. I literally filled a 3" binder. Then I sorted it all out and made a decision on how I wanted to treat it. The hardest parts are the initial diagnosis and then deciding what to do.
But, there are many of us here...that you can vent to, relate to, and bounce stuff off of. You're not alone...welcome. Now's the time to talk with family, friends, and significant others. The good news is that if you had to have a tumor...this is the one to have! It's slow growing, and not cancerous! This gives you time to research and make up your mind. Hope this helps.
Gary