During my first Ramadan I only fasted some days and missed others due to my menses. I don’t really remember how many days I made up the year after that. I gave money to feed a poor person instead. Because I’m not sure if I did things correctly, do I have to repeat that fasting for a whole month again?
You do not have to repeat the whole month, just try to remember approximately how many days you missed, and fast these days as a compensation and try as much as you can to fast Mondays and Thursdays and the three white days of each month with the intention to compensate any day still missing.