Hi there. I hope I can help some. My 2 year old (3 in July) had his tonsils and adenoids out 1 month ago. We had our follow up appointment this morning and everything is completely healed.
My husband decided he wanted to stay overnight as my DS is a bit of a daddy's boy at the moment. He also was the one who went in with him when he got anesthetised and when he woke up post-op.
We had a very old copy of a picture story book called 'Good-bye Tonsils!' that we read repeatedly before the operation to prepare him. He became obsessed with it. We used it to talk about what was going to happen to him so he would have a little bit of understanding. There are newer versions out though as ours was nothing like what happened. The link here is for a 2001 copy and is a lot more acurate (from what I read there).
Good-bye Tonsils!We also bought him a toy Doctors kit to give him after surgery. (All our family bought his a small gift for being brave). He has used that many times to check our tonsils.
I'm trying to find the words to explain properly what happens without making you stress or worry more. I'm just going to list what happened with us (nothing bad) so you know what to expect. All kids are different though, so your son may have a totally different experience.
When he woke up from surgery, which only took 20mins

, he screamed. And I mean screamed. All the people in the waiting room looked at me and said "That must be your boy."

That was really hard as I couldn't be with him. My husband just had to try and calm him down. He was a bit swollen in the face/lips but there was no blood anywhere that we could see. Screaming didn't help and he basically screamed and cried all the way down to his room.
He sobbed/cried between sleeping on and off for most of the afternoon and night. They kept the pain killers up to him but don't give them much more than panadol and codeine. I think the most he slept was for 3-4 hours straight.
They encourage them to eat pretty much straight away and will offer them dinner and/or lunch depending on when the surgery was. We tried a few things but he wouldn't touch much until dinner when the painkillers had kicked in. Then the first thing he ate was an Anzac biscuit.
The next morning he tried some food but wasn't really interested. They like to make sure they are at least eating something before they send them home. He was still upset on and off the next morning, but had some ok time in between the crying and sleeping. We asked for custard before we left and he ate the whole thing as it was soft, cool (but not too cold like ice-cream) and soothed his throat. Make sure the painkillers have kicked in before you offer food otherwise it will hurt his throat too much.
Sorry, this is a long post so feel free to skip the mumble jumble in-between.
When he got home, he slept on and off for the first 1-2 days. Wasn't interested in food but did try custard now and then. The only thing he ate for nearly 2 weeks were Calipo mini icy-poles. The Dr said to let him eat what he wanted so that is what he had. With the occasional custard.
His recovery took 2 weeks as they took a lot out. They say 10 days - 2 weeks is normal. He didn't eat properly until pretty much the end of the 2 weeks. He didn't cry much during the days, just got really sooky. We were told to keep the panadol up to him every 4-6 hours, even if he seemed ok. When it was wearing off, he would start to get upset so we would dose him up. Usually he had a sleep when it kicked in.
Nights were a nightmare. We ended up holding him to sleep for the first 4 days. He also ended up in our bed as he woke every 2 hours in pain. We would just calm him down and cuddle him until we were able to give more panadol.
They mention about referred ear pain, but his was extremely bad. He would bang his head and ears with his hands at night and scream every 2 hours. I even took him to the GP to get them checked for infection but it was all from the surgery. Be prepared for that, as we had no idea the ear pain would be so bad. It started after a few days and lasted about a week. We rang about stronger pain killers and the Dr suggested Painstop. They may tell you about it in the hospital.
Then all of a sudden, just before the 2 weeks were up, the pain stopped, he started eating small amounts of food and was much better. Now you wouldn't even know that he'd had them removed. Oh, apart from not having tonsilitis every 2-3 weeks!

I think that is all I can remember. I'm don't know your son, but ours gets angry/cranky when he is sick. He was a bit painful during those 2 weeks but back to normal after that. If there is anthing else you want to know, please PM me. I'd be happy to help.
I wish I'd have know some of these things before we went in so I knew what to expect. We were lucky as there were no complications, recovery went well with no post-op bleeding, and no other 'extra' problems other than the post surgery pain.
Good luck with it all. It will be horrible for 2 weeks and then it should all be like it never happened.
Oh, and last thing I just remembered. He may throw up after surgery and it will probably be a big clot (though our son had been sick the week previous) and may do it a couple more times. It will likely be blood and then nothing. Just make sure you give him lots of kisses and cuddles, which I'm sure you would do anyway.