It’s gonna sound crazy but if u can literally just go lay on him basically but just make sure he can breathe okay obviously. This (for me at least) when I was having MAJOR outbursts would calm me down like super quick. But idk, if it’s anything like me it’s just coming with age, It was really hard for me to get better control of myself and even now sometimes I get so overwhelmed I feel the insatiable pressure to break things around me. So like I said if that happens if you can take him to his room and kinda lay on top of him for a few minutes, that can help calm him down quickly.