Valid advice- baby? Or no baby?

My whole childhood was turmoil between my divorced parents. In the last two years I lost my best childhood friend, tragically. 3 months after her death, my brother died in a tragic car accident. 10 days after his funeral, I had an abortion. Please no criticism. I've used birth control for years, I wasn't ready to be a mother- and am still unsure why it happened. Anyway, about a month or so ago my dad left my step-mom (who is more my mother, than my biological mother) and I. I have a 4 year old nephew who spends M-F with us after his half-day pre-school. I'd really like to have a baby. And this is why: I'd love nothing more than to be a mother, and to unconditionally love a child at this point in my life. If I do, I plan to raise it in my home with my step-mom as a stay at home mom until he/she begins school. I know if I had a baby, my family would pay tuition for private school, and whatever I'd be unable to provide. I live in a 5 bedroom, 3 bathroom house which my father left to me after leaving Also, I am so unsettled in deciding an academic pathway, I believe after being a mom I'd have a more clear idea of what I'd like to do as a career, and would be more motivated to finish college- for my child. Because my own biological family is so dysfunctional- I'd like to start my own idea of family and love. The only reason I can think of not to is: my age, 21, and 'baby daddy.' If he wanted to be an active participant, I would do everything possible for that to happen. I've been dreaming to be a mother since I was a child, and thinking of it seriously for years now. I have a home, money, insurance, love and time. It feels like a good time, because it's very important to me to spend as much time with my child before he/she begins school & it doesn't seem possible with a career. I refuse daycare. Is this irrational & ridiculous? Am I crazy for thinking that it isn't?