Normally when people think and talk at the same time they take pauses to formulate a sentence. My friend has a mild stutter where she can speak to any stranger in any situation and won’t stutter. But when she gets nervous she will stutter and face a difficult time like in interviews. I think you might have really mild stuttering which many people won’t even notice. Maybe if you calm yourself down before going into situations you think you might stutter, you might not even stutter (based on the mildness).