There is such a thing as seasonal shedding, so it's normal to shed more hair right now in autumn.
I recently cut my hair shorter (used to come down to mid back) because I got sick of seeing hair everywhere. If your hair is long, it also looks like you're losing more because there's more of it.
But being run down and low in certain B vitamins, iron etc can lead to greater hair loss, without it being anything scary serious. If you're worried, get some blood tests done.
If your hair is thinning, see your doc about it. Lots of hormonal causes too, especially for women.