True, but it is not when St. Peter was made pope. In the "get behind me satan" episode Peter suggested to Christ, unknowingly, the same temptation Satan used, that of temporal power without the Cross. Peter committed a worse offense, too, by denying Christ. He was, however, given the charge of the sheep by the resurrected Christ, which signified the forgiveness of his errors.
***but it is not when St. Peter was made pope***
Your right, it was right after he was "made Pope."