I have problem with cat5 cabling

First I ran a length of cable 30 metres to my bedroom 1 and and connected both ends to a wall sockets internally using my punch down tool, both ends look fine. I also ran a cable from bedroom 1 to bedroom 2 so my son can use same internet connection , i then parallel connected my cables in bedroom 1 against using punch down tool using same colours all the way through. I ran a Ethernet cable from modem to first wall socket close to it then at bedroom end used another Ethernet cable to connect pc, it wouldn't connect to pc so I disconnected bedroom 2 cable from bedroom 1 socket. I connected bedroom 1 to pc and it worked, but how do I connect bedroom 2 (obviously cat 5 cable bedroom 1 to 2 is in place) As soon as I connect one wire from bedroom2 I loose Internet connection!