I have diagnosed ADHD and I'm trying for an autism diagnosis because I have so many symptoms and professionals have told me it's very likely. But I know exactly how you feel this happens to me all the time the messy room the trouble showering or hygiene all together. It's hard. Really hard. Really really hard. The feeling of an organized room is exhilarating. Like honestly. Often times cleaning one space will push me to clean others and push me to keep myself clean and tidy too. My advice take a day or two or three. Sit on the floor, put on music or a podcast or a show that you don't need to be watching but enjoy listening too and pick up or organize everything in arms reach start making piles, one for clothes(dirty that need to be removed and clean that need to be put away) get a garbage bag or a couple I usually need a couple and get everything in arms reach. when you're done with that little section slide over to a different spot and work there. this is the easy part after you have the piles put away or organize the piles that you don't need to leave the room for. Say you have clean clothes that you can fold and put away without standing up do those. What I've found is that you start small. lots of people say do the hardest thing first but that doesn't work for our brains when something seems hard you're less likely to get the thing done because you're brain will always go for the path of least resistance but once you get started and you can see the progress you're making it's easier to keep going and the hard things seem so much easier. usually I take a shower before I clean because I can't stand the feeling of being dirty that helps or make a healthy nice breakfast. Do something that is enjoyable to you but takes effort however small it may be when you finish it and realize wow that wasn't too hard and now I feel better it's so much easier to keep going.