cat extending neck purring and making weird grumble noises

About 10 minutes ago my cat came to me purring, but he stops and extends his neck and opens his mouth, i thought it would be a hairball or a cough but i am not sure, he is getting drowsy and im trying to keep him awake, he keeps tasting his mouth, is this an emergench? Please my anxiety is threw the roof!?

I am a human doctor, not a vet but the symptoms that you give, particularly the fact that your cat is getting drowsy, suggests to me hat you should treat it as an emergency and take your cat to a vet as soon as possible.

Thank you so much!
I think he was tired he is on the move now, still moving his neck I think he wants to vomit, I am trying to find a officr open today sunday to take him