Mate I am completely empathising and it is normal.
I was buzzing for my little boy. I had this utopian vision and the reality is far from it. Dex had colic hardcore and basically screamed and then slept an hour or two.
If I am being honest , and I take no pride in it, I hated the las for weeks and took every opportunity to leave the house.
It came to a head when I came in from work and my partner was desperate for a pee kid feed. I was given bottle and baby and she disappeared. He wouldn’t take the feed and she came back and said ‘do this or that’ or something to that effect.
I snapped, stood up and gave Dex back and went ‘he doesn’t fucking want it from me so what’s the fucking point’ and walked out in tears.
She cried. I cried in a separate room.
Roll on 4 years and giving myself a slap of at least give it a go Dex is amazing.
Remember you are more than a father and the life you had before still exists, it just needs a tweak.
Much love brother.