Worried about my kitty :(

I don't know to be honest. But hopefully it's nothing serious. I'll pray your kitty will be alright.

go to the vet hurry he will die tell me what he ate or when was the last time you took him to the vet from halobunny619 im a vet

Socks should be ok, Did anything happen before he started heaving? like he may have been in a fight with another cat or something. Have you notice that he's only doing it at certain times/places? (say like if he's only heaving near plants or other Pusa or something,or only at night? Or is it at random?) Also how long does the 'heaving' last before he acts normal again? If you notice a sort of pattern of the times and places that he's heaving(eg: he only heaves at night), it might be something as simple as asthma, try talk to your vet about it if you haven't already and they might find something. :)