@Confusedandtired21 - You are absolutely nailing it as a parent!!! You have no idea how bloody amazing you are.
When things are going great, it's easy to be a super-duper parent. But when you're struggling with overwhelming conditions yourself, quite literally at rock bottom, while still supporting two autistic children - and all the fighting that involves - you are a fucking rock star.
To manage all of that, and still keep on putting one foot in front of the other is real success. Your child WAS picked up. Your children have been fed. No one gives two shits if the house is a bit untidy right now. You are doing the important stuff even when you are at your worst. And that's why your children need you - because there will be no one that could ever give as much to them as you clearly are.
Also, no one will understand the struggles that your neurodiverse children will face like you do. You ask how the blind leads the blind - it's because you know what it's like to be blind. Someone who has never experienced it can only guess what your children might experience or what they might need. What you perceive as your weakness is actually a great strength, even if it doesn't feel like that right now.
You need your ADHD meds. Please contact the GP surgery - maybe ask to speak to a nurse if it's easier? If you've been taking ADHD meds and have now stopped, OF COURSE you've crashed. Give the Lithium a chance to increase to a therapeutic dose - but you should be on your ADHD meds too.
Executive functioning is a shitter when you have ADHD, even when you're on top form, which you're clearly not. You only have to do the basics for now. Takeaways every night are fine, it's not going to be forever. You just have to get through this period. It will pass. It will. Don't panic about anything else, just focus on what you need to be doing right now. Do you need to sleep? Did you get yourself a drink? Something to eat? Do you need to put your child to bed? One thing at a time. Just one. And then the next.
I'm autistic and have ADHD. I've two DC who are both autistic. I know how tough things can be. Do you have any support directly related to autism/ADHD? That might be really helpful right now. The NAS have closed their helpline but there is a link to local resources. I think it would be helpful for you to have support from autism/ADHD experts, alongside the mental health team.
www.autism.org.uk/what-we-do/help-and-support
I just checked and I'm not anywhere near local to you or else I'd come round and help x