Saying Havdalah on Thursday

Q: I remembered today (Thursday) that I forgot to say Havdalah, what should I do?
A: It is too late to recite Havdalah. One can say Havdalah up to three days after Shabbat - Sunday, Monday and Tuesday. You can repent: regret the mistake of the past, and accept not repeating it in the future. This means that one should establish means in order that it does not happen again.