If you're currently in no position to go private, then the first thing to do is get in contact with your GP. My local GP allowed me to fill in some details about my issue, and they'd contact me to dicuss it further.
I was asked to collect some questionnaires to determine the impact of any symptoms on my life. Now, at this stage, you should request to be referred via 'Right to Choose' along with a suitable private clinic, such as PsychiatryUK. I think I did this but was ignored and referred to my local NHS psychiatry unit with it's wonderful 4 year backlog (18 months on the list so far!)
I had to appeal to doctor's initial decision as there was a lack of evidence, so be prepared to provide school reports etc to defend your stance.
Get on the NHS/Right to Choose waitlists as soon as possible, and then you can pay for private if the funds come up first! Hope this helps!
I can wake up, and go 10+ hours without meeting/requiring a single human need, but as soon as I then acknowledge that I should be doing those, all the sensations hit me at once.
Nothing quite like having to prioritise all base needs at once!