if you have judgement in your favor is there a deadline for you to collect is this meant for the defendent or both

Although I am not familiar with Michigan law, it doesn't sound likely to me that a creditor would only have 21 days to collect on a judgment.  In NY, for example, a judgment creditor can collect on the judgment for 20 years.  If you mean that the judgment requires the judgment debtor to pay a certain sum within 21 days, it is the the judgment debtor's obligation to make the required payment within that time period (although the creditor may often be willing to wait a few extra days), and if the judgment debtor does not comply, the judgment creditor can institute collection procedures against the judgment debtor.