What's wrong with my camera?

Not camera repair man, but that sure sounds like some type of problem with the IR filter in your camera, or part of the filter. Try your camera in different light intensities, such as a dark room, fairly dark room, dimmed room, light room, medium bright room, bright room, and sunny day, and log if the colored lines may have consistent behavior of showing up, if they do, it's your IR filter. They are easy to fix, but if you don't know anything about electronics you may snap your camera when you open it, so I wouldn't open it. The IR filter can be replaced fairly easily in most cameras though. If your camera is still under warranty send it to the manufacturer they will fix it if it has not been internally opened. If you have any other questions feel free to write me ghostlyencountersva@yaho.com.