Calm is a great mantra!
DS13 had a totally frustrating first day of High School, hated being in a new building with new kids. I remember being overwhelmed the first few days too, back in the day. The second day he came home feeling fine.
It doesn't help that I don't know the people or the building or the 'customs' either, but I got my 'stalker-powers' on and did some sleuthing, so there are fewer 'covered-holes' now. For example, his 'assistant principle' in charge of his grade has a name that when pronounced, sounds like a 'dirty word.' I had my 30 minutes of freaking out over it, and now I can be sure to warn DS in advance, so he doesn't have to deal with that in public.
Love to everyone at this challenging time!
Grinity