First and foremost, I hope your son is OK.
That said, at least you got to see a full GY!BE set and four awesome songs from Neurosis. I realize that neither band tours that much, but chances are you'll get another opportunity to see them again someday.
I feel your pain about the family getting in the way of shows and metal in general - I have four kids around the same age as yours, and any time I go to a show it's a major accomplishment to get a hall pass and I somewhat feel guilty the entire time, but luckily my wife acknowledges that I need my releases from time to time and gives me some leeway. Still, I can't just run out to every show like I used to be able to do, and so if anything it makes me appreciate the ones I do see that much more.
Just hang in there and know that one day you just might be going to shows with those little bastards - and that'll rock more than anything you've experienced thus far. My oldest is getting close to the age where I might be able to take him to something tame such as a post-rock show, and I can't wait for the day to come. For now it'll just have to be limited to movies, sporting events, monster truck shows, Indian Guides campouts and stuff like that.
8/10 Boris / Atlas Moth / SubRosa
9/8 Man or Astro-Man?