LED power consumption in theory and reality
Your PSU meter is only has resolution to 0.01 A (10 mA). The actual current could be anywhere between 5 mA and 15 mA for the single LED.

Switch your yellow multimeter to mA range, connect the leads into the correct sockets and wire the multimeter in series with the one LED and get a more accurate measurement.

Paralleling LEDs in this fashion is not recommended. The ones with the lower forward voltage drop will hog the current. Either connect them in series with a current limited supply or put a resistor in series with each LED to limit the current.