Scared of this planned pregnancy

I risk writing this, as I know so many women try to conceive for so long. I know so many have experienced loss, too. Please forgive me ahead of time. If anyone else feels this way or has felt like I do, please reach out. I’m struggling.

I’m a mom of a two year old boy, and I just started feeling like myself again. I love my little guy so much, and it feels like I finally got this SAHM thing down. Life has started to get easy again and I really found my rhythm. My husband and I knew we wanted two; that has always been our plan. We decided to go ahead and go for it, and got pregnant right away.

Although this was planned, and we are prepared in every way to bring another baby into our family, I feel nothing but dread. I hate even saying that. I’ve never felt so horrible about getting something I wanted. I’ve basically sobbed continuously for 24 hrs. I guess I just feel like I’m losing myself all over again, and that somehow I’m replacing my son. If it weren’t for gifting him a sibling, I most likely wouldn’t have tried again. I don’t feel mentally prepared for all that’s to come with newborn, plus a toddler.

I’m in a dark place, and feel so alone. My husband is so supportive, but really has no clue how I feel and can never experience what I have. I would love to hear if anyone feels like me. Did anyone feel like this with a positive outcome? Thanks so much.