I've had my peace lily for about three months now and I'm still figuring out its moods

I've had my peace lily for about three months now and I'm still figuring out its moods. It droops dramatically when thirsty, which is honestly kind of helpful—like it's telling me exactly what it needs. My question is whether I should be fertilizing it yet, or if I should wait until it's more established? Also, I've read that Spathiphyllum can handle low light, but mine seems happier near my east-facing window. Does anyone else find theirs prefers more brightness than the care guides suggest?