How a PIC behaves under overload conditions is unpredicatable but the usual failure is the output driver transistor in the top or bottom of the pin driver. It shorts and as a result the pin becomes unusable but the remainder of the IC generally carries on working. Drawing the extra current may have caused a dip in overall supply voltage though, that depends on how much current is available. Note that many PICs have brown-out protection that creates a graceful reset rather than random code execution. You also have to consider the total current drawn from all the pins, if the extra current to your LED pushed the total pin current over the limit there would be risk of permanent damage to the silicon. PICs are pretty tough though, I've seen them run too hot to touch and yet still work OK when the fault has been cleared and they have cooled down.
Brian.