Hi Vivian,
sorry about the growth news, but at least now the uncertainty is over. The bugger probably doesn't intend to stop growing, so it is better to deal with it now rather than later.
Like others have said, it is not as terrible as it seems. Be prepared for a long day for sure, but the procedure itself is not so bad. One more tip. As you know I had GK at the same centre. Have you asked who will be the doctor treating you? Don't assume that is will be the same doctors that did the consultations, because they have scheduled rotations, and it depends who is on duty that day. If you really want your doctor to handle your case ask specifically what dates he is in charge. All the doctors are good and competent, but I want to warn you so that you won't get a nasty surprise of meeting a doctor that you have never seen before on your treatment day.
Other than that, I would say try to keep your mind occupied with other things, so that you won't constantly think about it. Remember that with GK you don't see any results right away, so by the time you are done with GK, you really won't feel much difference anyway.
Marianna