Oh I really feel for you, DS1 had his tonsils and adenoids out in July, but it has been so so so worth it he is like a different child now.
He was only 2.4 when he had his op so it might be different for your DS but he stayed in hospital overnight after the op as that is when there is the highest risk of bleeding. My DH stayed with him as I had a 9 week old DS2 and it was heartbreaking leaving him but he was fine with his dad, he slept on a pull out bed right next to him.
The recovery for my DS was awful because he wouldn't take his pain relief (we had to get suppositories, useful to know about them in advance just in case this happens to you) I think if you stay on top of pain relief to the minute (every four hours) including at night the first few nights, and eat ASAP then it is much better. He needed to sleep lots in the first week and we watched a lot of DVDs and bought him a couple of new toys and books. We weren't allowed to take him out for two weeks in case he picked up an infection while the tonsils were healing, he was bouncing off the walls by the end but they were quite strict about that, an infection can be really bad.
Also coming round from the anaesthetic was really traumatic, but I watched others on the ward coming round and they all reacted differently so that is down to the individual child. Some ate and drank straight away!
I know another two children who bounce back from the op, and kept on top of pain relief, recovered really quickly. My DS did take a full two weeks to recover, don't mean to sound negative but I didn't realise it would be so bad. Saying that I would still put him through it as he was so poorly so often and now he is much, much better.
Good luck 