I dread going to people's house for this exact reason. DD has just been flagged as possibly having SN, and at any rate is now having 1:1 at pre-school, but until 3 weeks ago nothing had been raised.
So, 3 weeks ago, I just thought I was a bad mother that time out didn't work for, and had no control.
She is 2.10. She screams, she has started a biting phase for the first time in her life (thankfully only with those who are stopping her reaching her goal ie, DH & I), the first thing I have to do is ask if my host has any shampoo at a low level, because DD will take the top off and squeeze it all over their floor. I could go on.
Believe me, I feel inadequate enough as it is, and cringe at what they must be thinking, but you just confirmed it for me.
And before you say "ah, but your DD has SN, and this girl does not." I would say 'how do you know?' Until 3 weeks ago I would have said that DD was NT but hard work. Now I, and the Area Inclusion Officer & Pre-school, suspect different.
Be gracious, the mum is probably cringing with every scream. She will not relax, and she will not be oblivious, she will just be trying to seem as if she is taking it all in her stride while you merrily judge her