multi touch not working after DIY power button fix

i went ahead and fixed the power button of my ipod nano, just like many other it broke and didnt turned on/off the screen, but after i finished the fix i saw that the multitouch on the screen wasnt working, could it be because of something i did wrong or did i &&^&@@ up my screen, there no visible differences in the image on the screen but i think i see some deformations on the back on the lcd (i think that its name),