MSBTGrl ~
Hi. I'm sorry to learn of your post-radiation side effects and hope they lessen very soon.
Doctor estimations of side effects from SRT are usually based on their experience with other patients and the 'average' radiation patient.
My neurosurgeon (who debulked my large tumor) and my radiation oncologist worked as a tem using 'fresh' CT and MRI scans to precisely focus the radiation beam on the tumor and avoid peripheral nerve damage. They opted for the FSR method (26 sessions with a total of 27Gy) and I was told that any side effects would be minimal. They were. In fact, my radiation side effects were virtually non-existent. I was told that I would lose some hair at the radiation site but on the day of my first session, the radiation oncologist informed me that he had re-calibrated the radiation and I would not lose any hair. I didn't. No nausea, very minimal fatigue and no headaches during or after the 5 weeks of sessions ended. Like you, I trusted my doctors - and they were correct.
Of course, we're all individuals and no two patients will experience the exact some outcomes to surgery or radiation treatment (in my case, both). Obviously, treating an acoustic neuroma is never 'easy' and it would be naive to expect it to be but I'm sure your doctors told you the outcome that they had usually seen with other AN radiation patients and did not lie or keep anything from you. Still, because radiation is a lot less complicated (and invasive) than surgery, many AN patients are dismayed when radiation isn't quite as 'easy' as they may have expected. If it were, few AN patients would ever opt for brain surgery to address their tumor.
I'm certainly not a doctor and would not attempt to explain why you are having these side effects from the radiation treatment you received. However, I assume that you'll consult with the doctors that treated you and try to receive some answers to your pertinent questions regarding these after-effects from the SRT. I hope these issues resolve quickly and that your recovery can proceed in a more positive way. Keep us informed as to how you're doing. Thanks.
Jim