Advice scored 0 points on PIP assessment with autism and other disabilities

I've just received my decision letter. I scored 0 points despite living with autism, spine problems, severe osteoarthritis, anxiety and inflammatory bowel disease. Autism mainly effects social interaction and emotions. I have no friends, can't socialise and only drive locally. I also wear a prescribed knee brace and am waiting for a consultation for joint replacement.

The assessor decided that because I can drive, do short period of online voluntary work and am a carer for my ASD son that I do not meet any criteria. Also mentioned anxiety can't be an issue because I don't take drugs for it. I self referred to local mental health trust for therapy but ended up making a formal complaint as they missed calls. I tried medication years ago and ended up with heart palpitations and mood swings.

I've asked for a mandatory consideration as decision letter didn't even mention autism or my disabilities. It had duplicated text and mistakes in it and said I didn't mention difficulties during assessment. I did and we talked about pain, panic attacks and mobility problems.

I'm prepared to ho to tribunal just yo bring an end to the constant paperwork and to finally get a definite answer.