Yes it's natural!
It's called "To feel energy while energy work" that's all.
well, if you can see the energy is leaving, I would suggest that you collect it back. if you have enough skill and training to see and feel it, then it should be quite easy for you to re-claim it. I would wonder how you can patch it up, but either way, you should have no problem to get the energy flowing away out of this hole to flow back into to you. we all spend so much time here learning energy rasing techniques and what not. this is a strange question indeed !
The other night i was doing some energy monipulation and i gathered alot of energy around my hands and i pulled it into my palms and pushed it out of my finger tips and molded it into claws. I then sliced my aura and it looked like alot energy was streaming from the place i cut my energy body. After a lot of the energy spilled away i felt kinda drained. Is this like normal because it was kinda strange for me.