not, um, terrible. at least you started small. you could almost do that in mspaint tho... but i give it an (A) on the effort. i think i can photoshop fairly well, not nearly as good as some of the pros on the boards such as ov3n. i can do sweet collages and mix car parts around, and somewhat change the colors, but not quite seamlessly like others.
keep at it and just keep playin around with all the different features. once you get the hang of it, it can be really fun.