Making the enormous jump from MS Paint to GIMP/Photoshop is really hard. I tried once and only had GIMP downloaded for 20 minutes before I decided it was too hard and I'll never figure it out. Uninstalled it. Didn't try again for almost a year.
Hydra mentioned a program called Paint.net which is almost as user friendly as MS Paint but with the better functionality of GIMP/PS. Paint.net isn't as versatile as GIMP but it is a lot better than MS Paint, so I think it's a good bridge between the two.
Paint.net uses layers, which is important. It also has a few of the basic tools and effects that are really good for editing images. If GIMP seems confusing, you might try out Paint.net (it's a program like GIMP, I don't know why they have the .net at the end) and make the transition after using it for a while.
Only downside is there aren't as many tutorials for Paint.net as there are for GIMP. The tutorials will help a lot to learn new things.
But anyway, it's a cool little hobby, hope you keep getting better!