Yes. It is a chemical response by the mirror neuron network to observed behavior in others. On second thought, it is actually an involuntary emotion.
Emotions are strong physical effects driven by the unconscious, so saying involuntary emotion is redundant.
Empathy consist of the feeling "as if" the individual would be the distant individual (so 2 bodies feeling the same effects but only one is impacted by the real effect).
I have experienced myself this kind of empathic feeling (feeling is not emotion, it is not related to strong physical effects but just effects).
Saying that i suppose you just say, "he is kidding, saying he has experienced empathy as if this would be something special".
Yes, sure, because you are perhaps (or not) doing confusion between empathy and emotion.
You can have emotion when you see someone being hurt, but this is not empathy, it is much likely a behaviour that permit to avoid the same fate.
You have empathy when you see someone cry and you cry.
You have empathy when you see someone being hurt... and
you feel yourself the hurt
and the pain going with the hurt.
You feel really the pain, like if the pain were yours, it is no only emotion, it is real feeling of the same qualia.
This work with our species but it works with other species too.
You can per example feel the pain of an injured animal, at the same place where the animal is injured.
You can not understand empathy is you never exeperienced it.
There are ways to become empathic, but it is difficult to remain empathic in a world like our, where there is so much pain (if you are extremely empathic you will suffer from the pain you have around you and you will not even be able to do anything any more... because you could cause pain.)