I ended up shouting!

Feeling pretty bad today. 
After weeks of wrangling my son finally got an appointment with the GP, He has ASD and struggles with his organisation very badly. He was up ALL NIGHT last night, then exhausted by the time the appointment came around at 9.25am. It was impossible to get him there. He fussed and had two meltdowns. I hasten to add the appointment was at his request, He made us late for the appointment, but thankfully the GP agreed to see him.

He wouldn't go in on his own and of course couldn't find the words once he was in there to say what ailed him. Consequently, we have had to make another appointment and go through the whole thing again next week.

What upset me was that in all the drama it took to get him there, I lost it and ended up shouting at him, Normally, I take a deep breath and bite my tongue, but after several 18 hour days this week alone between the boys, I just snapped.
He looked startled, but frankly i'm struggling to deal with his yoyo decisions and mood swings. He's developed sleep Apnea along with his night terrors and sleep talking so an average night for him is a disturbed one.
Although, he's still under the sleep unit for his sleeping difficulties I'm told this is part of the childrens section and he will soon no longer be eligible because of his age. He can no longer take his Melatonin because of the Apnea so he has no resolution.
I know he's exhausted, but frankly so am I!

Does anyone have any suggestions to ease his angst? Perhaps a natural remedy that doesn't affect Apnea. I've tried a few herbs recommended by a friend, but to no avail. I'm seriously considering going back to the Osteopath with him to see if I can turn the volume down for him, but other than that I feel i'm floundering