Replaced WiFi Antenna. Now screen display is showing weird rectangles.

I replaced the wifi antenna, which involved me removing battery, screen, etc, and reconnected it and rebooted my phone. Now my screen had these weird vertical / horizontal lines that form colored rectangles. The color changes depending on the background (white for the Apple logo when restarting, red for my wallpaper). I see no actual background, just these colors. Reconnected all of the connectors many times and made sure all contacts are good, still the same result. HELP!