Speak to your health visitor. There’s services like CAMHS which can help teach you techniques to deal with extreme behavior
@Mel yes we do try. There is no distracting him. It's like he's in a rage that he can't get out of!
My daughter born Aug21 used to do that back in April, spring time for some time. I don’t have a solution but to make you feel better it stopped… hang in there.
We went through this. For us we needed bigger consequences. It was "if you don't stop by the count of 3 then X toy will be in the bin". After following through twice she realised it was in her interest to listen. Now the second she starts to escalate we send her to the naughty step to calm down (imperative that you are calm too) and within 30 seconds she'll come back and say "I'm calm now/I've done my breathing" and we quickly discuss why she was sent away in an upbeat tone and thank her for calming done quickly. I think we had gotten so bad because our threats had no meaning. Now they do!
Distraction! Do you ask him what's wrong? Hungry, tired, in pain, bored, sad are generally the reasons for a tantrum. With my eldest running a bath would snap him out of it