There are many ways to go about asking for help. Firstly, there is no "correct" channel....
You can certainly contact your GP and book an appointment with him/her to ask to be referred to a psychiatrist/psychologist/social worker in your area who you can see.
If that is not something you are comfortable with, you can also contact local organizations that can refer you to someone, or may have someone on sight. Where are you located? Perhaps I can find an agency near you.
Remember - if you are in crisis - don't wait for an appointment. Go to the nearest emergency room or call a hotline if you feel safe enough at home to do so.
Good luck to you.
"You shouldn't be afraid to change; instead be afraid to stay where you are. If you let fear of change rule you, you will live never knowing there is a fuller life out there that is yours for the taking."