Ok i figured it out!
Arduino cant switch between analog pins (they are multiplexed) as fast as it would want to read them!
the solution is first swithcing the pin (analogRead(pin)), then puting in a delay(10ms is fine) and then reading the analog again to get the real value!
It seemed to me that the analogs were somehow connecting, i had no idea that the Atmega only has 1 ADC for all analog pins...
Cheers!