Should I Call It Stress?

I don't know how else to describe this terrible feeling other than "stress". But it's worse than stress, kind of overwhelming. I love my daughter so much that going to work brings so much anxiety. I feel like I should be home with her but also feel a responsibility to be at work. I can't do both though.

I got a call from my boss yesterday asking if I was ok..  I didn't realize my stress was obvious! I try to hide it, especially at work. She said that I've been under-performing at work and not doing as good as she knows I can do. I know Charlotte is in good hands with her daddy but I still can't help but breakdown when I'm not with her. Please tell me I'm not the only one! Before I had her, I was planning on moving up and eventually be a store manager but the second I held her in my arms I felt like everything I thought was important was ridiculous now compared to my new responsibility.
 I know that part of that responsibility is helping provide for my family so we can buy diapers, medicine, teething toys, and clothes for her, and give her a roof over her head. I already know that. But I feel like teaching my daughter and watching her grow is more important than having money. Knowing that I am nurturing my daughter myself and not relying on a friend or paid sitter makes it worth just staying home.
But it's essential I work if we want to get Chris through school. The faster he gets done with school and gets settled into his career THEN I can stay home. But that isn't for a while longer. By then I'll have missed things like her first steps and first words. Is it selfish for me to want to stay home even though we need the money? Even though it is the ONLY way we can get Chris through school? Both are very important.
I have two choices; quit and stay home with my baby and make Chris work more or work full time and let Chris go to school full time.
I'm completely and utterly torn.
Help?!

Thanks, rant over.