I suspect this little red cort is Dermocybe sanguinea also known as Cortinarius sanguineus.

Need to look at photo of gills, and base of stipe. And get a spore print on this one. But if the spore print is brown, this might be a Cort. of the subgenus Dermocybe. There are a number of red capped corts here in CA, and most have yellow or orange brown stipes. One thing is that most of these will stain your fingers red when you rub them.