If you constantly have headaches from the weight of your hair, it might be too long.
Again, I'm really lucky here - I also have fine hair but a lot of it, and it has very little weight to it. When I had it cut from past waist length to shoulder-length, I had all the comments about how much lighter it must feel. But honestly it felt almost exactly the same. The only difference was brushing it - my brush would shoot off into the air too soon because I'd forgotten I didn't have more hair to brush!