Design on Computer

Okay, I came to understand that it's not that hard, and turns out pretty well, to design bags on your computer, with the simpliest graphics program, Paint. I started just out of boredom and I made a few, so take a look, and tell me what you think:

Also, I'm thinking of taking a course in bag designing. I looked up around the net, and found some options. If you know of a good school that teaches bag designing, let me know, or recommend me on one. Thanks!