I'm in pain.
Chronic pain
Pain is interesting to me. It's been interesting to me since I watched House M.D. House had chronic pain which he dealt with by popping Vicodin like it's candy. Even though it is suggested that he was a good doctor before his leg went bad, it is also strongly implied that the pain made him who he is. A doctor that "takes no prisoners". At that point I didn't make any connection to any experiences I had, even though I had chronic back pain.
I then broke a vertebrae in my back in a climbing accident. I was climbing in a bouldering gym. They have a tarp cover a mattress, and the tarp had a tear in it. I fell, the tarp didn't break my fall, and I hit the floor under it. Laying there for a few seconds I wasn't sure if I'd ever walk again. I was lucky, the vertebrae healed without any need of surgery, but I did have to wear a brace for a couple of months any time I was not laying flat on my back. Let me tell you, the worse part is sleeping a full night on your back without changing positions. It makes for horrible cramps and major discomfort.
That's me in a back brace.
Ever since the accident, I've had to deal with chronic back pain, worsened by the fact I wasn't very active, and spent a good 14 hours a day on my computer. But I didn't quite get what chronic pain is and means, yet.
Fibromyalgia
Fibro was my first encounter with chronic pain. I've known several women who suffer from it, and through it I've discovered what it means to have chronic pain, how it affects your life, how you deal with it. Chronic pain I have felt is not in the same ballpark as Fibro. Pain is also subjective, it is measured by how it affects you, not by some absolute scale of severity. I've been in a sort of relationship with one, and am in a relationship with another, my precious 
From having those women in my life, and being exposed to all this, I have come to learn about the spoon theory. I have learned about pain scale. I have even come to learn about emotional pain, depression, and how it affects us in a very similar manner to physical pain. I have also come to understand my own chronic pain better.
I love what I have learned from my relationship with
My back hurts. It's usually about a 3 on the pain scale. I can ignore it. Put it out of my mind, and forget about it for a while as I do stuff. Usually remember it between activities, when suddenly nothing occupies my thoughts. Sometimes it cranks up to a 5, where I skip doing things because I want to avoid the pain. I avoid chores when I'm at a 5, as much as I avoid fun things like board gaming.
Good pain
So that was bad pain. It doesn't really serve a purpose. In the case of Fibro, it's the nervous system going haywire and sending pain signals to the brain for no apparent reason. My back pain isn't useful, it doesn't help me in any way. But there is good pain. The pain you feel when you get burned is good, it tells your brain to move the hell away from the heat source as fast as possible. Without that pain, you could suffer a lot more damage.
I lost my balance on the bus the other day, fell, and hit my chest against one of the seats. I have a broken rib. My broken rib causes me pain, but it's good pain. The pain let's me know I need to lay down and rest. I shouldn't strain myself. I shouldn't bend this way or that, and let the bone set back and heal. When I don't move, it's barely a 2. When I move wrong, it can be an 8, but that 8 is very short, and so doesn't affect me aside from making me avoid doing that movement again.
So thank you body for supplying me with a good tool to keep myself safe. I just wish it didn't go wrong for some many people.