Moved to a new house with kitten - he's scared

Hi all, I just moved into a new house with my 6 month kitten. I set up one of the bedrooms for him, and he's got his food, litter box, toys, carrier, scratching post, bed, treats, and I put the 8hrs of relaxing cat music on. I took a shirt and rubbed it on his cheeks and head and rubbed it around the house at his head level.

However, the problem is the house is very echo-y and you can hear footsteps all the time when we walk around. It's also a new house so there's construction in the neighbourhood constantly, we're still moving things in, installing appliances, unpacking stuff etc. so there's a lot of noise. My fiancee's parents are also staying for a week to help out and he doesn't know them. I also can't stay in the room and comfort him all the time because I have to unpack, move stuff, etc. It's going to be full of activity for a few days at least, most likely a week. 

He got a chance to sniff the whole house when it was quiet and empty and he was fine sniffing everything, tail was up, seemed pretty brave, but then he went back to the inside of his carrier, curled up and looked absolutely terrified. 

What else should/can I do? I don't want to buy a feliway diffuser or experiment with calming drops and stuff until after a week when it's less hectic and I can monitor him in case of reactions or anything. 

He's also going to spend his first night alone in his room (which looks like a nursery at this point lol) since I have to meet the movers at the old place in the morning.

He eats but I haven't seen him drink or use the litterbox, and it's been over 12 hours. He purrs (50% out of stress I think) and alternates between cuddling with me and staying inside his carrier. 

Am I just totally over-worrying? I spoil him... thanks!

Are you feeding wet food or dry food?  Cats that eat wet food do tend to drink less water.  How often is his water bowl cleaned and re-filled?  Cats do not like dirty water and sometimes do not drink water if it is sitting out too long.  My cats would not drink enough water out of a bowl so I got them a fountain.  If you do not have a fountain though now may not be a good time to add any more changes.  

Are you using the same litter you were using before you moved?  Some cats do not like it when you switch brands.   I would keep any eye on the litter box a little bit.  Perhaps someone else will have a better idea if this is an issue yet.  I am not sure about this.

It is great that you set your cat up with his own space in your new place.  The last time I moved over 14 years ago I did not know to do this.  My poor cats hid in my basement with the litter boxes and would not come upstairs at all.  I had to put their food and water in the basement and go down there to spend time with them.  I think they would have been less frightened if I had done that.  

He is adjusting to a new space with a lot of new noises and may be feeling a little overwhelmed.  I think it is ok to leave him alone for one night.  After that though I would check on him to make sure he is eating, drinking and going to the bathroom.

Hopefully you will get more advice soon from someone with more recent experience.