Are sins counted against one who threw stones at a thief to recover stolen money from a woman?

You did well by saving the woman's money from the thief, based on what the scholars have stipulated regarding the obligation to rescue a Muslim and their property from whoever intends to seize it unjustly. It would have been better to return the money to the woman without pelting the thief with stones if possible, otherwise, there is no sin upon you, Allah willing.