If that gear was not in it's proper position it would cause a gear stripping noise, with any luck you haven't done any real damage at this point. Wouldn't hurt to pull that cover and make sure that gear is in it's proper location. The noise could be that gear out of place against the starter.

I learned all I need to know about life by killing smart people and eating their brains.
Eat right ,Exercise ,Stay fit, Die Anyway!