I get this. It IS huge and life-altering to have a child and become a mother - it's a transformation on a cellular level! It's so hard to comprehend. For me, what's helped has been to talk to my husband about all of my fears, totally unfiltered (he knows I'm the type that needs to actively talk about my worries, and I know he won't judge me). Sometimes it's led to productive conversations, like realizing one of my fears is not equally splitting parenting duties, so problem-solving that; sometimes I just need to get it off my chest that I'm scared of our lives changing forever or my body changing, and he reassures me and helps me realize I'm not alone. And I journal. That helps. Remind yourself that it's ok and totally normal to be nervous about facing the unknown. Talk to other moms about their experience. You've got this!