flowering help

my plants just showed preflowers, have been in flowering for barely over a week.

they are heavy indica, should they be done about 7 weeks from the day i started 12/12, or should they be done in 7 weeks from when they showed preflowers?

I am not an expert but I think most Indicas flower for 9-11 weeks. best to get yourself a jeweleys loop, I didn't have one for my first grow and it got over ripe. the trichs were pass amber and the whole plant was s**t! good luck with your grow. aloha