8yo autism negative self talk

[Mumtoboys1]

My 8yo has autism and has developed some pretty bad negative self talk in the past year or so. For example, if he gets told off his response will be something along the lines of ' I guess I'm just the worst person ever ' or the other week in the park playing football he fell over , threw the football and said ' I'm never playing football again ' which to later on he wanted to. He will even go as far as saying he wishes he was dead if he loses a game.
It just makes everything so difficult I can't even discipline him without him reacting this way so it makes me not want to.

Even days out if he falls over (he's quite clumsy) hurts himself in any way he will just walk off (no sense of danger)

But typically in his baseline self he's very intelligent if I talk these things through with him he's very receptive as to why he needs to stop doing these things and then when they happen its like we never spoke.

Does anyone have any suggestions as to what is going on or what could help?? Thank you

My 10yo son is just like this. His first reaction to anything new is always a negative reaction and catastrophises everything. Even if he does something before, if his first reaction has been negative then that's all he associates it with. He's been going to a football class for the past 2 years and because he got overwhelmed with the amount of people there the first time he was there he has to be coaxed every single week to go even though he comes out with a smile on his face!
The negative talk and saying he would rather be dead tends to come when he most stressed, maybe something has happened at school or he's thinking about something that we've no idea what. We talk to him about it and then he realises that wheat he's saying isn't proportionate to what happened but he just forgets about it because it's not the most important thing to him at that moment.
He also does the same thing when he's hurt, I got told that it's to do with him being understimulated by pain so just kind of brushes it off. Over the past year though he has come more aware of danger thanks to Cubs and him wanting to walk to school himself so had to prove he could cross the roads responsibly.
I don't have any answers I'm sorry, I've become more understanding to him since his diagnosis and going on the Cygnet course and I think me being less stressed by his behaviour has reduced his stress so the talks we have about his negativity and such seem to go a bit better.