I know what you are going through right now. We were right there this time 1 year ago, so consider this me speaking to you from your future. :) When you pick up your first placement, all your fears will disappear. Instead of worrying about what could happen to you, you will worry about what could have happened to this child without you stepping in and stepping up. You will grow closer to God every day as you act as Jesus' hands and feet to feed, love and protect these precious, innocent children. Months from now, you will get on your knees and thank God with tears streaming down your face for not letting you give up because you can't imagine your life without this child or children in it. You will look at their beautiful, smiling faces and listen to their laughter while they run around like "normal" children. And then you will thank God again.
To quote a fellow foster mom blogger,
And look what God did when I did that." - Mama Foster