I'd say your done, based on your recipe and time fermenting. If you want to take another sample shake it a bit,(you sample could be saturated with a bit of CO2. let it sit on the counter for 20 min. The hydrometer are corrected at 60F I think, so try to get your sample at that temp after it sits out for a while. I dont like using the correction factors at differant temps, but thats just me. Afte the time its been fermenting I dont think your gonna get much more out of your yeast, unless you were fermenting cold.