Why am I not excited for something I've always wanted?!

Chelsea
We are 12 weeks pregnant after trying for about 5 months. My entire life all I've wanted to be is a mommy. I've wanted to grow my best friend and feel that unconditional love. Everyone I know has always said I will be the worlds best mother. I believed it. I wanted it. My husband wants a baby more than anything too and knows I will be a wonderful mommy. But now we are here, at 12 weeks, I've battled depression, anxiety, and HORRIBLE 1st trimester symptoms. We planned on announcing our pregnancy yesterday and I just ended up not feeling like it. I'm not excited at all like I want to be, like I thought I'd be. I don't know if its my depression or what. My husband and I love each other very much but we have problems just like everyone else. Are these little problems causing uncertainty. I really don't think its normal to feel this way about something I've only dreamed about. I'm stuck in a miserable rut and I'm praying I'm not the only one. What is wrong with me?