Some Lactarius species are easy to recognize to genus simply by their colouring but at other times you'd need to see some bleeding from a damaged area to make Lactarius a plausible guess. I can't think of a Lactarius that looks like this and there is no bleeding. Given the size, shape and colour I wonder if this is a species of either Inocybe or of Entoloma (and it could still be something else, since there are a number of genera of small, brown mushrooms).