So I made the move to kegging. Got my first beer on tap and it was fantastic checked all the fittings no leaks. Left it for about 4 days come back to get a beer open the door pull the spout and nothing, check my CO2 tank and it is empty. So my question is the beer is flat now can I recarb it and it be ok or is it ruined. I lost the pressure due to the intake fitting going bad.