HELP! I just noticed some things that seem off about my hamster!

[rocknrage]

While I was cleaning his cage, I noticed that his face seemed different. I believe he's starting to lose hair around his eyes and nose. It's slightly red, but that could just be because I've never really seen his skin before.
Another weird thing is that from the waist down, his fur is turning a chesnut brown (the rest of him is black with white spots). It's a beautiful color, but should I be concerned about it?
Inside the ceiling of his igloo was all wet with bedding stuck to the top. I had never seen this before. At first I thought it was pee, but I have no clue how he could urinate upside down, you know? What could it be? Another weird thing about his pee is that it's a very yellow, cloudy liquid. It's been this way since I've got him, but it seems to be a little extra yellow and (I'm not sure if this is actually in his urine or not) when I looked into a recent puddle, I found little specs of something, like very small stones. Could he be peeing that or do you think it was just something left there and peed on top of?
Finally, his wheel was covered in dandruff-like flakes. What could that be from? I don't really see anything on his fur.

More information:
Male, Syrian.
I've had him for about a year, but I don't know how old he was when I adopted him. He was already full grown.
Being fed VitaSmart Hamster Formula.
Recently started giving him Wild Harvest Bake Shop Cupcakes Treats (only occasionally, I know they're not very good for him).
I've been using Carefresh Complete Natural Paper Bedding for a long time now, but I noticed they've recently changed their formula. It seems to be a different shade, texture, and scent. The packaging is exactly the same and I didn't even notice until I opened it up and started using it.

Could these be contributing to these problems?

[Sm_banks]

Take him to the vet IMMEDIATELY. Anything could be wrong but only a vet will be able to help.

[Erin.R]

Darker colored hamsters fur will lighten, black hamsters turn brown in spots. If he is having hair loss you should get it checked out for mites but he may also be losing fur a little with age.Since you are not sure I would keep an eye on it to see if he is actually losing fur. Igloos can get condensation build up inside of them, they are poorly ventilated. You could take that away and give him a cardboard tissue box with a door cut out and this should solve that problem. Hamsters using is very thick, yellowish and milky, completely normal. Not sure on the flakes but Carefresh is so dusty anymore I would try changing bedding see if the white stuff goes away;0

[cypher]

It does sound as though he could have a problem with mites, it might be worth getting that checked out at the vet.
His pee sounds perfectly normal.
It could just be condensation build up in the igloo, plastic houses aren't really very healthy, or if does pee in there & then had a dig around in the substrate some wet substrate could have got pushed to the top.
Either way I'd get a better house for him, either a wooden one painted inside with non toxic paint or as Erin suggested a cardboard box.