I see you're in Germany. In the US, house wiring does have neutral and hot wires. 120 volt wall plugs are supplied by one of the two hot (black or red colored) circuits coming into the house. The hot wire is 120 volts over neutral (white), so the 60 Hz voltage swing takes place wholly above neutral. A third "ground" (bare) wire is present for additional safety. The other hot wire coming into the house is 180 degrees out of phase to the first hot wire, so when you have a socket that uses both hot wires, you now have a 240 volt circuit for appliances like stoves, dryers, AC and the like.
Back to the original subject, wall sockets can be wired incorrectly and this can be one cause of tingle the OP is experiencing. Hence, $10 or $20 for a wall socket tester is a good investment.