HELP PLEASE my DS is failing!!! Answered

I've had my faithful Hot Rod Red Nintendo DS for a long time now... at least 4 years or more! A couple of years ago, my friend smashed the top screen with his forehead (don't ask...please, just don't). I sent it in to Nintendo for repairs and paid $70, and when it came back everything looked fine. This year, however, i have been noticing that something is wrong with the top screen. The colors aren't shaded right, like they don't blend into each other like they should. Also, every once in a while the screen flickers into false colors (light colors turn black, dark colors turn that freaky blue color). ALSO, every once in a while a shadow of what's happening on the bottom screen appears on the top screen. How weird is that? The best example is when I'm playing Animal Crossing, and as I'm walking around I can see a shadow of my character, the trees, buildings and everything on the top screen. They aren't colored in, just dark shadow images. It hasn't been that bad, but recently it's been becoming worse, and i'm afraid it's going to fail completely on me soon. I'd get a DS Lite, but a new DS, the DSi, is coming out sometime next year. Should I pay to get it fixed? Should I attempt fixing it myself and risk ruining it? Or should I just wait a whole year for the DSi, and hope that the screen holds out? Someone please help, my DS is pretty much my main console, and the discoloration and shadows drive me nuts when I'm playing MarioKart and such.