Irena your last post made me think of 2 things. Maybe at least one will help.
When DD was little she had the most amazing preschool teacher. She was in a lab program at the local high school. No predetermined tasks, no "samples" to copy. Everything was purely child driven. Her last year in the program she would go in every day and "write", direct and star in a play. Every day. She would dictate the story, cast it with her classmates and they performed it before dismissal. She used all of her strengths and was the happiest she had ever been in her life. When she started real school this avenue of expression was closed off. She couldn't write thoughts down and there was no room for free expression. Now that she is in a really good out of district placement she is back to having the freedom to explore what she wants through 1:1 enrichment. She also is radically accelerated for her reading comprehension strengths (5 grade levels ahead). I can't tell you how much calmer, more confident and happy she is. She is now involved with a musical theater company and in rehearsal for her 5th real musical production. She will still occasionally come up with a play idea but only occasionally. It is also much less frequent that she bursts into song or starts to dance either to a tune in her head or one she she hears. That tells me that these were in some way coping mechanisms and she no longer needs them since she has a good school placement.
The other thought I had for you was about my DH. He is an artist and art professor. Over the years I know when he has struck upon what is going to be a new, very successful series of work because he enters "the zone". He disappears into his studio and barely emerges for days at a time. He prefers a windowless room because he has no concept of day or night when this happens. I periodically go in with food (always simple hand held items like sandwiches or bagels because I don't think he would even be able to handle a knife and fork when he gets like this.) He eats them totally mindlessly never taking his eyes off the piece he is working on. This goes for days at a time. No sleep. No breaks. No rational conversation. Does it seem strange to an outsider? You betcha. Is it something to be concerned about? Nope.
I think your DS will have to learn to contain his impulses and learn to compartmentalize his creativity but that will come with maturity. Yes it will seem weird to others but I think you already understand and accept that. I would say that unless/until a qualified professional tells you this is a symptom of a serious mental health issue you need to stick with your gut. And no, I personally do not consider a mainstream 2nd grade teacher to be a qualified expert on this.
