If he's actually eating real food, he's way ahead of the game! Lots of us are on feeding tubes at that point. Good for him! Has he got enough painkillers? I didn't even know what they weren't offering me till I broke down crying one day before a rads appointment ... they were saying "Wow, and most patients break down before this!" as if I had been trying to break some kind of pain record, when really I just didn't know I had options! And guys generally don't go for the 'break down in tears' thing. The urine thing sounds like dehydration, maybe? I don't know much about that, but I know they put charts up at camp for the boys in the summer so they can tell when they are dehydrated, which sounds funny but apparently is helpful for them. The darker, the less hydrated, I gather.

Let him know that hitting a wall is normal. Annoying and miserable, but normal. It stays bad for a few weeks after rads are over, and then it slowly starts to get better. He may need painkillers and anxiety meds to get through this part, if he hasn't got them already. And it's okay to ask for them. Ask for special nutritional formulas and prescriptions to get them, if he needs ... they can get pricey and sometimes insurance will cover it.

((hugs)) Sounds like you are being a good caregiver ... hang in there!