confidence boost?

Oil changes are very monumental right? ha Well this one was.  Sitting in the waiting area and I am reading my chronological Bible.  A lady across from me asks if reading the Bible in that form helps...I reply yes!  Along with a few other comments.  As I am talking I can feel my face turn a little red.  Why does that happen?  I am not embarrassed of Jesus.  Is it because I know that this could be an opening for the sharing of the gospel?  Is that what is frightening me?  Is it because I know that I can never explain how much God has changed my life?  The fact that a few other people are listening to our conversation in the room?  Obviously, the fact that my face turns red means that this is not just some topic that means nothing to me.  I want to be bold for the Lord.  I want to talk about Him with confidence.