CheyenneMoon,
Yes, the first fitting of the Mask is a different experience for sure, I am usually good with tight spots, but the Mask just threw me for a loop the first day.
When I started my first treatment, I did as what was mentioned above, I listened to music that the Tech had put on for me, and pictured things I liked to do in my mind and tried to relax, deep breathes and I made it. Each time became easier and at times I nearly fell asleep.
You can mention it to the Nurses that you may panic and they will work with you and give you something to calm down. Luckily, I did not need that, but others did. The main thing is to get thru this as comfortable as possible.
Yes, I would also think of my grandkids and that would bring a smile to my face and calm me. You CAN and WILL do this. It has been 10yrs since my surgery.
My Best to You and Everyone Here