Gotu Kola for Concentration?

This herb is suppose to help with memory and concentration. I like to take about 3000 mg a day, 3 days before tests and the day of tests for school. It seems to greatly enhance my ability to learn about maybe 20-30% . I get significantly higher grades while taking it. Has anyone else here taken gotu kola? What have you experienced?

My side effects where easily aggravated, headaches and constipation.

i have taken it and felt great on it with no side effects.

I have not taken it but heard it is good for circulation/vessels.