Hello - I'm so sorry to read you're feeling overwhelmed and confused, and definitely ignore any nasty comments on here!
I think there is such a big cult around motherhood that it feels very isolating for the many women who've never gone gooey eyed at the sight of babies. I'm 15 weeks pregnant and honestly I'd put myself in the camp of "if I wasn't with a partner who really cared about children, I'd probably be fine without them". My sister was actively upset at the idea of me having kids!! - we're a practical, active family who like our careers, freedom and peace and quiet... In honesty for quite a lot of my first trimester I felt extremely sad at the loss of my past life, made worse by not being able to enjoy a last hurrah of coupledom before the baby comes because of this stupid virus. If the people around you are expecting you to be over the moon and baby-mad right now, it will feel really unsettling if those aren't your feelings. Is there anyone you can talk to openly and without judgement about your uncertainties? Either a friend who's on the same sort of wave length as you, or a close family member? Having a child is a massive life change - when I got my positive test result my first thoughts were "what have I done" rather than tears of happiness, and that's despite having deliberately come off birth control. (tbf I wasn't expecting the BFP to happen within 6 weeks).
As other posters have said - do talk to your midwife. It may seem trite to say "hormones hormones blah blah" and you probably don't want to hear that because it may seem dismissive that your very real feelings are passed off as a chemical byproduct of pregnancy. There is support out there and they will try to help you sort out what's hormones and what's not.
Have you talked to your partner? If he's so overjoyed perhaps you feel like you can't raise the subject? I do feel like the decent men out there understand how different it is for women... try giving it a go? He may have his own worries about becoming a dad, and generally nerves about the changes in your lives. You're a team! He's there to support you and I bet his adoration and love for you has seemed more intense since you're doing this amazing thing.
Babies and children are hard but the bits afterwards are great... The way I see it, the next few years are going to be difficult - women bear the brunt of this - but the long term game is worth it!! I think about my mother's life and how important she and my sister are to her... or any older person in my generation and how important their family is... and I'm so grateful that hopefully I will have that to look forward to in the second half of my life.
Please reach out to your midwife!!! and take care.xx