My minecraft skin won't change?

This has been happening for a while now but whenever i play minecraft on vanilla i'm a steve but i have changed my skin back to a panda skin on multiple occasions and it won't change or on one occasion it did for about 5 minutes then changed, it works perfectly on forge(modded minecraft) but for some reason it won't work on vanilla, if anybody can tell me if its a bug with minecraft skins in general or if its something to do with my computer as i have recently got a brand new gaming pc so i hope its not that option.

It happens to me also, other people can see your skin but you can't see it yourself. Try using minecraft 1.7.10 and it may fix it, if not its nothing to worry about Mojang will probably fix it soon.

Are you making sure to check if the client's Play button says "Online" because the Client has to connect to Mojang's Servers to get your character data, which includes skins details.

Thank you, It turns out it was because of something to do with Optifine 1.7.9 so thanks a tonne. I shall continue using 1.7.10:)