No network on my MacBook air?! Pls help!

Hi !

I have bought the audio cable replacement because my audio did not work. I installed it and now I have audio :X But when I started my MBA first it freezed... Then I realised that I have no network to connect to. It says airport off. I turned it on... Still nothing. It says off all the time. I restarted a few times and one time it did ask me of what network to connect to... I selected my wireless connection and I had internet for 5 min. Then again airport off. I reinstalled mac and at some point it freezed. Even the cursor didn`t move. Restarted manually. Installed mac again. It took abaount an hour...weird... Finally mac has been installed. Got to the create new account window, I input my name and password... Click continue and nothing. All buttons grey. I waited 20 min still nothing. Restarted manually. Mac loads... and all is good but no network. This time no network at all... System preferences-network ... the list is empty ! Clicked on + to add a network but in the list is just bluetooth... No network off any kind. I really really really don`t know what to do :(( Any ideeas ? It all worked before I installed the audio cable. But I was extremelly carefull and followed the ifixit tutorial to the letter. What could have happened ?

Thx....