Hi Windy,
I also had some unexpected swelling a few days after my radiation treatment, only it was my right eye (AN is on the left). I woke up with it too, and it was quite alarming because I thought things were going great. My radiologist felt it was most likely due to trauma from the headframe. There had been a problem positioning the headframe and it had to be taken off and put back on, so I had a few more holes in my head than expected. Ice, tylenol and time took care of most of the swelling, but I have to admit that there's still a very slight "droop" on that side. None of my doctors are concerned about it, so I'm not either. As long as the AN isn't doing anything, I'm satisfied.
As to the steroids, I didn't take them immediately afterward either. I was given them via IV during the treatment though.
Hang in there....the weeks after treatment are a conflicting time. The treatment is finally over and done with, but it's a long wait to see the results. Have you seen your Primary Care doc about the swelling yet? Let us know how you're doing.
Betsy