compare the orange cable end to the photo on step 9 here:
iPod 4th Generation or Photo Headphone Jack Replacement
Is the square black connector still on the end of the orange cable? If not, then you accidentally peeled the orange cable off of the connector, which is still in its socket on the logic board. You will need to order a replacement headphone jack board, and use tweezers or needle nose pliers to GENTLY remove the damaged black connector square from the socket on the logic board.
If the cable and connector are intact, it should be a simple matter to snap it back into the socket on the logic board - the cable routing will guide the connector to the socket with the correct orientation.