I know this is 2 months old, but that's also what self-harm made me feel. I felt joy from both the pain and the feeling after the fact.
Most of my friends who self-harmed did it because they liked the feeling of all of it, not JUST the pain.
I always did it because it felt good and I liked the way it looked, but it became very dangerous once I started cutting to the hypodermis layer of the skin (which is the last layer of skin above muscle).
Anyways, I hope you haven't been self-harming in any way ^^