Try not take it personally about the professionals referring you on. I remember when ds used to have people come to the house when he was younger, play therapist from the LA I think she was, well she wrote to nursery asking if they had any concerns with me or ds' home life and who to contact if they had. I got a copy of the letter, he has moderate autism and learning difficulties, nothing about me or his home life caused his problems and since she used to visit the house I thought that would be obvious to her. I found that really hard to not take personally when I did everything I could for ds.
I think it's probably just standard procedure. I do feel we are more under scrutiny when we have SN children though, I've thought that plenty of times! Anyway as you said SS were happy with everything with you, so fuck who referred you!
I do totally understand your mental health taking a battering with sn children though, I flit between coping to really struggling and then back again, it's the hardest thing I've ever done.
You have issues going on with your own health, and other areas of your life on top so you really are doing bloody brilliant in my book! Even if you can't see it yourself.
And hell yes regarding volume. Ds stims all day and he's incredibly loud! I've put his ear defenders on my own ears more than once. (Would this be a possibility for you?) I've got really sensitive to noise over the years, probably because there is never much silence. Really does drive me mad!
Hope you start to feel better soon OP