stop worrying about tax evasion,, u are not a big fish.
however u have good potential to be bigger or help charities sell their stuff.
so seek out any free Tax returns training for the self employed. Search any local Business start up initiatives designed to help people becoming self employed ( which includes self assessed tax returns )
Some places will assess and diagnose you privately but it costs. The free option is go to your GP and ask to be referred into the NHS system for evaluation and diagnosis.
There's a good info graphic about how to get diagnosed if you Google "how the girl with curly hair got a diagnosis", that takes you through what happens when you go to your GP and ask for a referral to the nhs.
