How do I fairly feel about this?

In December 2021 my mom suddenly passed away and my dad ended up getting with someone else in September of 2022 they met in a grief group.

well they are getting married this September.

I am 24 and i just had a baby girl in march, me and my fiancés have been together for 7 years and was planning to get married as well, my dads soon to be wife fawns over my baby (she has a 12yr son already)

Today I was in the kitchen making lunch and there’s an Amazon Alexa on the counter and it had popped up recently deliveries and it showed a pregnancy ovulation kit!! She is 49 and my dad is 51

I am SO hurt. My dad is actually my step dad and he’s never had his own biological children but he’s been with me since I was 4. Them having a child together makes me feel as if it’ll take away from my own baby who’s my first it’s so weird to me! I feel like it’s selfish but this is all a personal opinion and I don’t know if it’s right of me to feel like this. I just had a baby and supposed to be married this year too but it feels like we can’t have anything special while they try to have a baby plus a 25k+ wedding while we can only afford to go to the court house to be married.. just feel like the moments are getting taken away..

How should I feel about all this I already know about the wedding OK but the ovulation pregnancy test kit?!

Is it wrong of me to feel like this? Should I just be happy for them and move on?