2.5 Weeks Ago I Was At The Beach. I Was

2.5 weeks ago I was at the beach. I was using 15 spf and noticed that my feet are getting red very quick. I then applied more sunscreen and covered them with sand. When I came home, I noticed a very strange pattern of the sunburn on my legs. Didn't hurt too much, just like a regular sunburn I've had before. Those parts that were red started peeling about 7 days after I was at the beach. Now, 2.5 weeks later, they both peeled, however, I still have that strange pattern that's not getting tan, it's simply red, looks like it just burned, but there is no pain. Should I be worried??