i hope they are both doing much better. the sleeping is normal, from the anaesthesia. i had two females spayed and it was uneventful. my cat was spayed and she wanted to be quiet and sleep. she also wanted to be in my lap and to knead, whereas usually she isn't a lap cat. None of them gained weight after spaying.
i would be worried about alfie's crying, but i hope by now that is passed and he's ok. zack never had any sign of pain after surgery, he slept off the anaesthesia for a long time, he didn't seem very happy with that altered state, he looked depressed. after that, he didn't show pain, but pain was really important to his vet, she made a big deal out of it, she gave him an extra pain shot and gave him pain pills (tramadol) to take around the clock at home for the next 5 days. I only gave him one pain pill the following night, just in case he hurt in the night, but he never showed any sign of pain. The vet wanted him to be comfortable and not disturbing the stitches. but he did not need the pain pills. Some dogs will. It depends on the dog and the surgery. Each time is different. I guess that's why my vet wanted to be prepared for it. pain meds are constipating though and i didn't want to give them if they weren't needed. I had enough poop issues with zack early on to last a lifetime.
Zack was neutered at 7 months and did not gain an ounce until he was a year old when he gained about a pound, but it wasn't from the neutering. It might be normal growth, he was only 14 pounds before, but i think it was mainly because i stopped exercising him and stimulating him as much so he slept more. He's 16 pounds now at 14 months and he is not going to gain any more weight because i won't feed him enough for him to gain more at this point, but he's not fat. You can easily feel his ribs and spine. but he's not thin either. he eats between a cup and a cup and a half a day. anyway, i'm working on the exercise thing too--it's so important.