Neutered cat not sleeping and still humping: Is this normal?

Some pets will be more active once they wake up from sedation. This is usually temporary and will usually wear off in a few hours. It is very important to try to keep his activity minimal. I recommend to have him contained in one room with his litter box, food and water. Try to pick a room that does not have tall furniture or anything that he may try to climb or jump off and on. You may need to hang out with him until he calms down. Playing classical music may also help and decreasing stimulation in general. If he is still hyper tomorrow, you may want to call his veterinarian and ask about a sedative. I hope this is helpful and please feel free to post any additional questions.

It is possible that Toby is still disoriented from his surgery or acting different due to the surgery. I would recommend placing him in a bathroom with a litter box and some water so he can have a dark safe area to rest. It should be fine to wait to eat until tomorrow I hope that helps

His castration wound looks good, I see no evidence of infection and he is apparently not licking it either. He should indeed be back to his normal self after three days. You may want to take his temperature with a digital rectal thermometer to check whether he has a fever. should he have a fever ( 103+F) he will need to go back to the vet for a recheck. However the whole excitement from being at the vet's, the anesthesia, the drive in the car may just have caught up with him today. If he is not eating, drinking or does not want to play on Monday, I would also take him back for a recheck.

Once all the male hormones have left the younger one's body, this should stop. It sometimes takes a few weeks (3+) for all the male hormones to go. Now that the younger one has no more testicles, there will not be any significant testosterone production anymore. Your older fellow is a sweetie and obviously not too worried and might see it just as play. As long as they do not have serious fights, I would not worry about it.

Sometimes kittens can actually get hyperactive in response to the sedatives that are used during the procedure. You definitely don’t want Ginger jumping around or being too active. I recommend to shut him either in a small bathroom or a large dog crate. Make sure to provide his food, water and litter box. Hang out with him if you need to until he calms down. I suspect the sniffing is also just a side effect from the sedative. If he does not seem normal by tomorrow, call his veterinarian. If he seems ill or really out of it, go ahead and call his veterinarian today. I hope this is helpful and please feel free to post any additional questions.

Papoose will be in pain from the surgery, but hopefully the pain medication the vet gave him is helping. I'm not surprised he's not laying on his stomach, it will be tender from the surgery. Keep an eye on him tonight, and if he is still this way in the morning, give his vet a call.

Any change at all can make a kitty restless. He will just have to get used to the new room, the new cat and also his body has to adjust to the new situation (no more testosterone). This should subside soon. Restlessness by itself is not a problem, but if he does not calm down back to his normal self you may want to have him examined by a veterinarian.