Arduino voltage on 5V and 3.3V pins have doubled

measured with a multimeter. the power supply is 12V (4x AA) on the Vin and GND (also used for the servos)
schematic (only pins 0 and 1 have been used for hc 05 rx/tx and 7 more servos)

the measurements have been made between the GND and the 3.3V/5V pins