Can you get at the circuitry of the LCD? If so, smell it. Does anything smell burnt? (like an OLD television) Sometimes you have to get your nose in real close to smell it. If it smells like ozone or burnt circuitry that's very bad. If it smells, chances are really good that it'll take a professional to fix it, if it can be fixed.
If it doesn't smell check it over for fuses. You may have burnt one out. Those aren't too hard to replace.
Then double, triple, quadruple check your wiring. Use a meter and check where you wired it up. How many volts are you getting there? Amps? Is it what you expected? Is the polarity what you expected?
If all else fails, leave the screen sit unconnected to anything overnight. It may act normal in the morning.
Past that, I dunno. Good luck!