Whenever i change my skin, it says i'm already logged in

I'm not sure if this is a bug or not, or if anyone else reported this, but whenever i want to change my skin, i quit my game (( so it's not running)) log into minecraft. net , and change my skin

HOWEVER, after a wait a few minutes, so the skin can take effect, I try to load the game, but it says i'm already logged in, and that i have to Sign in again.

I'm not sure what causes it, but It is annoying, and the first time it happened (( i really don't change it much)) was back when the heart bleed thing came to light (( for some reason it kept my skin as default, so of course i changed it))

Does anyone know what causes it?