LED power

I have a custom board, that basically consists of a nrf52832 module (ebyte), a button and a LED. The LED is connected as in pca10040: VDD->220R->LED-> ground to p17.

I assume (!) that LED power consumption should be [VDD-Voltage drop]/Resistance= (2.8-2) /220=3.6ma, however the whole BOARD consumes 2ma when LED is on and 1.5ma when the LED is off. It puzzles me.

Is this because all pins are configured as s0s1 so the LED pin just sinks 0.5ma only? Is it safe to leave things like that?