I have 3x 3s battery and 1 x 4s battery. I always used 3s, but I was seeking for more juice.
When I connect the 4s my copter become very unstable, impossible to fly, if I switch back to 3s everything goes normal.
Do I need to make a esc calibration?
You will need to retune you PID to change from 3 to 4s batteries. Without the retune it will be unflyable because with the voltage change you are basically upping all your PID parameters.
Also remember to use smaller props with the 4s. Else you might risk frying your motors.