replaced headphone jack. now it doesn't work. whats wrong?

i just finished replacing my headphone jack in my iPod Nano 6th gen. however when i go to turn it on it does not. and when i plug it in the screen rapidly flashes white. what happened and what do i do to fix that.

crwdns2934089:0crwdne2934089:0 crwdns2934093:0crwdne2934093:0

crwdns2934109:0crwdne2934109:0

crwdns2889612:0crwdne2889612:0 0
crwdns2934285:0crwdne2934285:0