Okay thank you.
So I can advise you on the symptoms, but a formal diagnosis is quite detailed and requires a detailed assessment with a psychiatrist.
There is a diagnostic criteria which I will try and explain.
So a diagnosis is considered if you have 5 or more of the following: (6 or more if under 16yrs of age though):
-doesn't give close attention to things, or makes careless mistakes, so for work, school etc
-difficulty holding attention during a task
-difficulty listening when someone is speaking to you directly
-difficulty following through with instructions
-difficulty with organising
-avoids tasks that require some mental effort - finishing a book, completing work etc
I will double check to see if I have missed any, but these are the main symptoms or signs of ADHD. Mood is not often related, unless your mood is directly affected by issues relating to the above issues. Otherwise this could suddenly fall under depression given low mood can certainly be responsible to a lot of those issues I have listed.
I hope this is of some help to you.
You can get referred on the NHS which is normally 1-2years wait, privately it costs about £500 for a full assessment. But I would first consider counselling to help identify some of the issues first and then deciding which direction to take.
Please feel free to ask any further questions.