Coral reef burn

A year ago March, I was swimming at Ixtapa Isle. I noticed 3 red streaks on my upper thigh and thought I had missed the area with sunscreen as it looked and felt like a sunburn. Later on for a couple days the area would be sore if it got rubbed wrong or I slept on it. The streaks were raised like a welt. They too became dry and darker red/brown and I thought they would peel and that would be it. Nope, they stayed there for at least six months. Still slightly raised, but did not hurt at all. Now, after 1 year believe they are gone. A friend looked up jellyfish stings and mine looked just like one of them. There are many different kinds.
PS-out of curiosity I just checked to see if my streaks were gone. Amazingly, they are still there, faint, but still there. Crazy. Hope you heal soon.

Terry