I share a few of the symptoms by members above when anxious/distressed/depressed - upset stomach, headaches, nightmares, sensitivity to noise, dizziness, nausea, pins/needles/numbness and my pain threshold does lower.
But the main symptoms when depressed by major traumatic life events would be a "severe lack of motivation" to do anything. Severe fatigue. I have to force myself to do the basics, push myself constantly, cry a lot, feeling no joy in anything, seeing no light and just wanting to go to bed. Everything seems like an insurmountable task. Life seems an insurmountable task. That's when the depression is severe.
When mild to moderate the symptoms are not as severe, more a feeling of flatness - at times feeling overwhelmed by life but usually climbing out okay.