Freaking out.

I found out a couple weeks ago that I am pregnant with my third. I am just really freaking out. I am due September 24. My oldest will almost be 3 1/2. My youngest will almost be 2. Her birthday is November 29th. Can someone tell me that it’s going to be okay? I feel scared all the time. I have no idea why and I just need some words of encouragement. I guess tell me the good, the bad and the ugly.