I’m a mum and the regret was there for a while and I definitely experienced anger and PND. DH was a much more natural parent than me and could rock her to sleep whereas she was a ball of fury for me. I found the sudden 24/7 responsibility and exhaustion utterly destroying. I felt utterly trapped. But it does get better, it’s just very very slow.
So first bit of advice is to get to a GP and get some help. The anger though, if you feel yourself getting really frustrated put baby in a cot and go take a minute. Many a mum has had to do that to get themselves together.
When she’s calm take some time to just look into her eyes and coo at her. Sounds stupid but babies don’t give much back so you need to try to foster a connection from your own side, worry more about what she thinks of you than what you think of her for a few minutes a day.
Keep up the physical contact, skin to skin is good, babies like being held even when they are really pissed off, soothing noises gentle bouncing, gentle strokes on the back. Doesn’t mean they will stop crying but they will learn that you are there with them while they need you. It’s important that you learn to tune that out a bit, sing a son in your head. Imagine retirement whatever you need to do to tone down the noise hitting your eardrums.
sometimes you can be doing everything right and they still cry, she’s not rejecting you, babies cry for myriad reasons. Check that she has a clean nappy, isn’t hungry and has been burped properly (youtube has good clips of baby burping advice and tummy massage for constipation etc). One trick my cleaner showed me was rocking the baby gently while humming whilst looking away from them or with your eyes closed. Dd found that quite calming
get her out for a walk, sling or pram is fine, but even if its a quick 20 minutes outside it’ll do everyone some good.
the first few weeks were the worst time of my life, I spent a lot of time sitting in the bathroom crying. Unfortunately I don’t think thats abnormal. Newborns can be hellish little creatures sent from satan to break us. You must must must remember the baby isn’t doing anything to you, she’s here because you chose for her to be, none of this is her fault.
I had to work at a bond I had assumed would just materialise in a shower of glitter. It didn’t happen but I can’t tell you how I felt fist time DD giggled, first time she came up to give me a kiss and how she now shouts “I LOVE YOU MA!”. It will get better but you have to stick with it and keep trying.
google 4th trimester to help you understand where she’s at right now with her development. Also look up wonder weeks and check out developmental charts. It helps put it in perspective. DH approached it like a military operation and I think that helped, he had spreadsheets. I thought they were bloody stupid at first but then I could see a pattern emerging on nap times etc so got better at putting her down for a nap etc and feeding her on time etc.
Also remember that you and your wife/girlf are on the same side, you are figuring this out together, neither of you got a manual with the baby. Mumsnet is a good resource for various “why is my baby broken” questions (DH used it a lot).
hang in there. The main thing that good dads do is hang in there and keep trying, doesn’t mean you get everything perfectly right every time but it means you plug away at it.