That's the small Angie talking.
The world doesn't need the small Angie, the world needs the big Angie.
At first, you just have to stuff the small Angie in a sack and make sure she doesn't make an appearance during the phone call.
Over time, the small Angie will disappear...
But yes, he might question you. Especially if you're not confident.
And then you have two choices:
1. Realize you've lost control of the conversation and take back control. How? Ask a question
Well Mr. Prospect, that's a good question, and I understand why you're confused. But before I explain what I'm doing here and why I interview all of the clients I choose to work with, let me ask you a question... (and get right back on track) If you are asking questions YOU are in control.
2. Take the clue that he might be a bad prospect and end the call politely.
Remember, your job isn't to sell, it's to get to the truth about whether you two are a good fit or not.