Mind change?

I don't know if it's hormones but I just recently found out I was pregnant. My husband and I have been trying for a few months now. We were both so excited! But know I'm freaking out. I feel like I'm drowning. Scared of having another child. What the hell! I don't know if I want this now. I feel like a horrible person and I don't know what to do. I messaged my dr so hopefully I can talk to her about it. How do you decide if it's hormones or real feelings?