I missed the fasting of 6 days in Ramadhaan due to menstruation. I intended to make up for them starting from the second day of Shawwaal, although I was expecting menstruation on that day. I indeed intended to fast and about 12:00 pm I experienced menstruation. Am I required to make up the fast for this day as well? This means that I am required to make up the fast for 7 days instead of six.

All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad is His slave and Messenger.

You are required to make up the fast only for the missed days in Ramadan, the six days. As for the day when you experienced menstruation while making up the fast for these missed days, you are not required to make up the fast for it. 

Allaah Knows best.