We started homebrewing back in March, and are now on our 14th batch. The best lesson learned I can offer from my own experiences is that patience is a virtue. That's really tough to abide by, since I realize how anxious we all are to crack open a bottle of our first homebrew.
But out of the 13 previous batches, our most delicious beers have come from the ones where we've left it in the primary fermenter a lot longer than what you would ever see in any kit instructions. Because of work and personal travel, we needed to leave a saison in a five-gallon bucket for six weeks and cold crashed for a full week after that. We bottled it, and expected the worse (really thought there would have been some serious oxidation), but now we're enjoying what has become one of the best ales we've made so far.
We controlled our fermentation temperature (kept it at a constant 64 degrees) and left an American Pale Ale in the primary bucket for four weeks. We then dry hopped with 3 ounces of Mosaic for another week, and what resulted was the most-delicious beer we've ever produced.
My advice would be, check for FG with your hydrometer, but once reaching terminal gravity, give it another week.
You'll definitely enjoy the results.