Welcome Crayola64,
I think I can very safely tell you to calm down, take a breath and try, hard as it seems, to relax. You have time on your side at the moment. AN's are very slow growing in the majority of cases but they have been known to take on spurts occasionally. It's fairly routine for a neurosurgeon to examine your initial MRI, tell you what your treatment options are, and send you home requesting you come back in 6 months for another MRI. Waiting 6 months for your next MRI gives the neurosurgeon an idea on whether or not your AN is growing. This allows you time to do your research and become familiar with your options.
My ENT booked me for my first MRI that diagnosed my AN. I had a 3 month wait to see a neurosurgeon, followed by 9 more months of additional consults and tests for balance and hearing issues. In my case I had the option of surgery or radiation and just couldn't make up my mind. At the end of my first year my AN had grown from 1.8 to 2.4cm (mine took a spurt!) and I finally decided on Gamma Knife. I then had a 2.5 month wait for treatment.
I hope this helps you put the timing in perspective. You should certainly be able to attend your daughter's graduation in May. I remember feeling much like you after my diagnosis and found it easier to cope by taking many breaks and returning to read and do my research as I calmed down. The more I learned, the easier the research became. Discovering you have an AN, can be completely overwhelming, but it does get better and there are many of us who have had great success with either surgery or radiation.
One last note, the fact that your MRI has been sent to Pittsburgh, should help calm you as well. They have a fabulous reputation and you will be in good hands!
Best of luck,
Cathie