Could be that the water line between the water dispenser in the door and the water valve you replaced is frozen.
Pull the bottom two pans out of the refrigerator so you can see the back wall. Look for a coil of 1/4' plastic water line.
If it's frozen back there you can often warm it up with a hair dryer to thaw it out, it may take longer then you think to warm it up so water flows again.