I am also thinking hard about doing a course in web design. I certainly think you should weigh it up like everyone else said. My only worry about doing a web design course is what they teach. One of my friends has finished a web design course at college and he said his teacher printed of the html on sheets and the class just typed it out to learn. I think I would properly leave if I were in that class.
Look into the courses and make sure it's right for you. I will be doing the same