Yes, I had exactly the same. It started when my baby was three weeks old and always around 5pm, every day. It was horrible, frightening and very depressing. I had always had panic attacks and intrusive thoughts at times but it is ten times worse when you have a baby. I felt as though I needed somebody with me (& by nature I am independent and like being on my own so that was unusual), was so glad when husband arrived home from work at about 6.15pm most evenings. He was the only person (apart from MW), I told and then not the details which were too awful to articulate.
The midwife still called round occasionally and came one evening to find me sitting with husband, feeding my baby but with tears coursing down my face. I did tell her what I was experiencing and she said it was not unusual.
All I could do was tell myself that the thoughts were not real and would pass. I now know how to divert intrusive thoughts and panic attacks but didn't then and they were paralysing.
However it did pass after what seemed like a lifetime but wasn't really that long. Then I felt stronger and started to get back to 'normal'. Thank goodness.
I still remember those times and the memory is quite - sobering. When they cross my mind it is as if I am back there and I go very quiet. In my head I am screaming.
I never had another child; my fear was that next time it might be worse and beyond my control. I am thankful that I loved my child, there was no rejection, but I was afraid ....well, you can imagine. Eventually I made the decision to have no more children but enjoy what I already had to the full.
Good health, mental and physical, is so important and hormones being out of kilter after giving birth can cause many problems. It doesn't take much for some of us to go off balance and I am aware of how fragile I am in some respects so I protect myself. I have been very happy and loved bringing up my son so no regrets there. I generally don't talk about that period but it is there in my subconscious. I would always help anybody with similar difficulties, even if it was just sitting with them quietly, making a cup of tea. A gentle presence is comforting for anyone with such problems.
Diagnosis? Obviously post natal depression but in my case it bordered on psychosis for while, only bordered thankfully.
Build yourself up, good food, etc. Don't watch or read anything which might trigger your feelings. If you have kind relatives or friends who don't chat about nothing but will just sit alongside you for while, take advantage of them. It won't be for long. Welcome anything that makes life easier at the moment.
Deep breaths and try to relax. When this phase passes you will feel wonderful and grateful to be so much better; then you can move forward with your life.