Some more info about voltage/current electricity safety
When i forcibly stop these with my finger the current jumps to 0.7 Amps (8.4 Watts and more) and growing (the potentiometer i use to control current starts smoking). Now i read that 90mA are able to produce pain,


When you stop the motor, the current doesn't increase because it is flowing through your body. It increases because the motor's stall current is higher than its free-running current. 

You shouldn't expect to experience electrocution from this, because no current is flowing through your body (or at least, you haven't told us anything that would make us think there is current flowing through your body).