Ask yourself these three questions:
Did your depression start fast or did it slowly build over time?
Does your depression have a low, medium or high impact on your life?
Is this the first time you've felt depression, have you felt this way before, or has depression always been with you?
Do you feel moods like:
Sad
Irritable
Guilty
Do you notice yourself thinking things like:
Negative thoughts about yourself
Negative thoughts about your life experiences
Negative thoughts about your future
Do you experience things like:
Difficulty sleeping
Eating less or more
Being tired or fatigued
Do you do things like:
Withdrawing from other people
Doing fewer activities
Difficulty getting started doing things
Low motivation