Having second thoughts

I (24F) have a child who will be 2 next week, I’m a single parent, he was conceived via sperm donor, decided I wanted a second child, used same donor and am pregnant with baby.2, only 12dpo but bfp. I’m terrified of how life will change, if I’ll lose my bond with my son, how It’ll be, and I told my mom today and she absolutely shat on me, said I’m stupid and in no place to do this. I was confident in my decision until that chat. I have a stable income, home, car, savings, I am prepared for a second child but after her digging into me for how stupid it is and how much she wasn’t interested i am just so let down and having second thoughts now. What if this ruins my sons life? Having a newborn when he’s 2.5? I know being a single parent to 2 under 3 will be very hard but I am ready for it. I just feel so different and disappointed after talking to my mom