Signs of PND

[complexo]

Is it possible I had it (or still have it) and it has gone unnoticed all these years?
Daughter just turned 5...

It's possible to be depressed at any time and for any length of time.

So...how do I know if I am?

You don't. Everyone goes through bad and good periods quite naturally. Bringing a child into the world is a seismic shift in your life that can trigger feelings of fear or inadequacy which, combined with the fatigue of night-feeds and other stresses, can add up to a very low mood. But it can still be quite normal. Only a GP can diagnose an illness accurately. If you go to see them and explain how you're feeling they can give you a physical and mental check-up and then you can take it from there.