OP, gently. ‘That’s just who I am’ isn’t really good enough as a grown up. What if your child said that about not feeling confident or struggling with maths? You would help them find tools to feel better about them selves / move forward with their numeracy.
The same applies to our self growth as adults - if you’re getting messaging from your husband + Dr that you would benefit from some support then it’s really worth taking that on board.
your FIL sounds like a poorly regulated communicator himself. But if you can strip away the feelings of defensiveness and hear his messaging - it sounds like it comes from a place of concern for your family not intentionally unkind.
if you dig deep and consider - what is it that is making you feel ‘hyper and silly and loud’ - is it anxiety? Are you trying to fill space?
is being silly and loud like that something you would want to model to your son as a coping mechanism? Or would you rather he found other ways to calm himself.
you mention being told to put your phone away - again this sounds like a way of perhaps trying to hide from communicating? And your reaction to being reminded suggests maybe you feel about guilty because you know it’s not polite - or is something you don’t manage yourself around very well?
As I often say - the only thing we can change in our relationships with anyone is ourselves. If you are getting some strong messaging from DH and ILs that things aren’t working then it might be worth listening
edited - sorry didn’t mean to quote the above - don’t know how to remove that part!