According to the 16F18877 data sheet, the Absolute Total Power dissipation is 800mW, which is quite a lot!

Absolute Max current on any standard pin +/-50mA, but this does not mean you can source or sink on all pins at the same time that current. You have to stay lower than 800mW total.

In any case these are impressive numbers but for good reliability better stay lower.

Ioannis