I don't have a boy, only a daughter... But wanted to let you know that your fears are normal. My daughter is my everything and I have struggled with how I will be able to love another as much as her, and of there will be enough of me to go around.
I've sought lots of guidance from mommies with more than one, and I've come to the conclusion that once our babies get here, everything will just fall into place and we won't be able to imagine life without our newest addition.
The worries and the hormones cause me to cry sometimes too. It's pretty Normal though, so I've heard