You'd have to check trichomes with a scope to be sure. I'm surprised you've got brown pistils on week 4 of a strain that's supposed to flower 10-11 weeks, but I have seen Northern lights brown up early on and then REALLY start growing a ton of new pistils (and NL is part of the lineage of SSH). It should still go about full flowering time even with underpowered lighting. I'd think you still have a month and a half to go.