My cat is about 6 months old last night he was foaming and vomiting clear and tried to attack my son then he started banging into the wall then finally he just calmed down and sat there like nothing, he had all his shots and he is totally indoor I give him the same dry food and water all the time and the today I came home and there are two dried up green vomit stains on the floor I have an appointment for him to be neutered on Friday should I call the vet? Oh and he is also not eating the same food from last night is still sitting in his bowl.

Take your cat to the vet as soon as possible. This cat just may have rabies. Keep the cat confined as much as possible until you can take to the vet also. You do not want it to bite or scratch anyone. Handle the cat with thick gloves when transporting or moving into a carrying case. Tell the vet the symptoms before you go in so they can be prepared for the worst if necessary. The symptoms sound serious.

I would call the vet and see if he wants me to bring him in. Make sure that he is drinking water if not get him in asap.

Well, the symptoms do not look like rabies. The fact is that cats vomit... it's smtimes because of their sensitive stomach (for example if you change the food brand they may not tolerate it), smts pschological problems, sometimes some serious illness and generally because of hairballs... try fresh catnip, hariball cat food or hairball pills... however if your cat vomits too much and there is no hairball go to vet...

Yes, do take him to the vet. If he has had all his shots & is strictly indoors it is unlikely to be Rabies (not impossible, just highly unlikely). He may have gotten choked while vomiting, got scared and gone after your son out of fear. Also cannot rule out that he had a seizure. Regardless, the vet will want to know all this before he comes in for surgery!