Self-diagnosis: valid or not ?

For here? Absolutely. There are a bunch of people in that boat and the people with an official diagnosis aren't gonna dismiss someone because they don't have one.

For other places and parts of life you might need a diagnosis though. 

For here? Absolutely. There are a bunch of people in that boat and the people with an official diagnosis aren't gonna dismiss someone because they don't have one.

For other places and parts of life you might need a diagnosis though.