I think that the early years with DC are relentlessly tough. I do think the pressures change with time though.
Emotionally, at work, we're mentally adjusting our priorities before DC maybe a meeting running over or adjustment to work hours didn't matter, no stress.
After DC suddenly it's a wrist observing mental calculation can I still get to pick up on time, worrying about traffic to pick up etc. Our mind goes to DC rather than that whole business buzz phrase 'staying in the room'.
All these little pressures along with loss of work-related social connections whilst on maternity leave and any loss of sleep related tiredness can lead to us feeling more vulnerable. Then when we feel a bit more vulnerable we may come across as slightly more withdrawn or even, a bit defensive. Which doesn't warm others to us.
If the constant sickness and fear of going in has got to a really bad place you could see if there is any occupational health services at work or chat to your GP.
If its bad, but you still feel in control could you write yourself a life plan to get through the next months/ year. Give yourself little bonuses for each stage of work you get through. Even things like last working day of the month go out for lunch and get a magazine and and a coffee and take the time just for you. Have you got a rough medium term childcare plan like when DC is 18 months/ 3 years/ 5 years you could go full time. Or when they're at school childcare bills will be less so you could redeploy yourself at that stage.
Not all of life is exciting and sections of it are most definitely mundane. I found some of the young children bit like this.
At home couple time like going out for a meal stops being a spontaneous thing, finances are often more stretched, it means organising a baby sitter or taking lots of provisions for baby and mine weren't sleepers so quite often I'd actually have rather had a long quiet bath and watched a film in bed.
Do you and your DH get any quality time as adults together? Its so easy to find yourselves niggling at one another over who's put the bins out, whether nappies have been ordered etc and not stop and enjoy actually talking. There's also the whole house dynamic and role change thing with total renegotiation over the division of labour needed. Works smoothly for some, from the outside, but with my DH we ended up having to have a really frank discussion because I fell into taking on everything and ended up exhausted. It wasn't his fault as such just that he didn't offer and I didn't ask.
I really don't think feeling a bit dissatisfied with life post DC is that unusual. BUT, if the stress is really taking over consider chatting to your GP postnatal depression isn't just the week after baby is born and professionals really can help 