Hi chichirou - I can't really add anything to what others are saying. I am suffering from depression (but not PND) much too old for that - am a grandmother. I had a serious episode last Easter and have been struggling ever since with so many ups and downs, or blips as the medics call them. I am in the middle of one at the moment and I too have been crying most of the morning and am so sick of it all. I canhave 4/6 weeks ok and then a blip descends and you feel awful. Think that is what is happening to you now and it is unfortunately the nature of the beast as far as depression is concerned.
When you say you have struggled since your DD was born, it sounds like maybe you did have PND (there are a lot of young mums on here who have that) and it wasn't treated, and you have now dipped down again. You reallyneed to see a GP (don't wait till next Tues for the HV) you need a GP anyone to diagnose, but I think most of us on this thread will know that you are describing depression and it is a horrid deceitful illness. I say deceitful because it makes us feel that there is something we should be able to do about it, to feel we are failures because we can't cope, ashamed and guilty sometimes too. We don't feel any of those things with a physical illness.
It doesn't matter one iota if you cry when with the GP (this is exactly what I did) and you will not be acting any differently or saying anything different from what they have heard hundreds of times before. Remember 1 in 4 people will suffer from depression at some time in their lives. You will probably be offered ADs and I think they could help you a lot. They are not magic bullets and they take a week or so to kick in, but they can lift your mood so that you can cope better. ADs work differently on different people so sometimes you have to try a couple to find the one that works for you, but the first one you take might help.
Please make that appt and come back and tell us how you are. I've just stopped crying but still feel flat and unmotivated and am trying to force myself out for a walk in the rain!
Sending you warm wishes. Look out for Natsylou on these threads. She has had PND and many ups and downs and has recently started a group for mums with PND. Also there is a thread called "what does depression feel like for you" and you might identify with some of the things people are saying on that thread.