Hi Andrea-
Try not to get ahead of yourself just yet. See what they have to say tomorrow (bring a pad and a friend or relative if possible to take notes) and remember that most insurance plans allow for second opinions. Vic has a great list, but first of all you want to know how large it is. If this is your first test that has shown the AA, it's a "baseline" for you. The dr. will then recommend how soon to check it again. What caused it (hereditary, high blood pressure, bicuspid valve, etc) will play into the progression, or lack thereof if that can be determined. Some people's are small and don't grow much and they never need surgery. Others may grow more quickly and surgery will be indicated. The formula the dr's use is one that shows that when the risk of dissection or rupture outweighs the risk of surgery, then surgery is recommended. This is a situation where size does matter.
In the meantime, two important things to know are to avoid lifting or exerting doing anything you can't easily talk through while doing. Exercise is very good for you if your AA is small (power walk, jogging, light weight lifting) but not straining (heavy snow shoveling, crossfit, etc). Also, know the signs of what a dissection feels like (extreme sharp stabbing pain in chest, neck, shoulder) and call 911 immediately. Tell responders you have AA ad need CT scan as soon as you get to med facility. If that does happen, you have a very good chance of survival if you are treated in the first 4-5 hrs. Make sure your family, co-workers, friends know your condition once you have the info and that you have support and people to talk to.
This is a great group and lots of experience and knowledge are here. You should also look things up on very reputable sites yourself (Mayo Clinic, Cleveland Clinic, and of course, talk to your doctors.
Take care, good luck and try to remember.... you're lucky that this was found and you can do something about it.