24 year old with history of Mental Illness (UK)

Hello people. What should I do about my Psychiatriac health and well-being? I’m 24 years old male United Kingdom England and im disabled. I recently started taking Niacin tablets 100 mg but have now stopped today! And I have a diagnosis of severe ocd Tourette’s syndrome Autism (Aspergers syndrome). And I’m. Crazy. I’m crazy. I’m insane. I keep messaging lots of strangers and many medical specialists on the internet and on Telegram. What do I do? Can u pls help? They’re people who don’t know me. I’m very anxious. I was born with Autism Asperger’s syndrome but the Psych conditions are only last 6-7 years maybe 5. It was a long time ago. I had an mental health breakdown, ive never been admitted, but I am on psych medications too, I weigh 17 stone / 109.6 kg and I have blood tests once or twice a year. No one can help me. I’ve had MRI scans and ct scans. Nobody can help me. I’m sick. I’m crazy. I’m on an antipsychotic Medication called Risperidone and I also take Sertaline but these are prescribed Medications, to treat my mental health. What do I do? I’ve saw 3 Consultant Psychiatrists had cbt and I’ve saw two Neurologists as well one on the NHS and one Privately. What will I do? No one can help me. I drink 2-5 bottles 2 litre coke every single week, and I’m literally addicted to Diet Coke, and I’m feeling very forced to drink this every single day. My GP calls me once an month. I’m not having no other professional support or care, and no medical treatments. What can I do? Can u please tell me? I’ve also had horners syndrome since birth too. But now I am 24 years old. I will be 25 years old next year. I have like tired eyes and I feel fatigued lethargic sleepy and drugged up all of the time, and I have like pressure all around my head, feels almost like my pressure around my head is something to do with my eyes/glasses/horners syndrome, as I’ve been fidgeting with much frequency of my glasses so keep touching them repositioning them etc . I have a bad diet and I’m inactive and I. Don’t exercise I’m not employed and I’m on governmental money. I live just at home with my dad and my dad is 66 years old and is my carer. I have also saw Endocrinologist and an Clinical psychologist in past too. As well as a few other specialists and experts. What can I do?

I have a big belly and you see I feel very sick and tired and sleepy and poorly. What shall I do?

I feel like I’m insane. I know I am.

Please help!