How Can Sunburn On The Back And Stomach Be Treated?

Hello, On Saturday I spent all day in the sun and, like every time, put a lot of sunscreen on but still got burnt. Some of yesterday, not enough to be noticeable though and all of today I have had the feeling of pins pricking my skin. This is mostly on my back and some on my stomach but it is becoming more frequent and painful. I would normally ask my parents as they re working in the medical field but they re both not home yet. The feeling of ants crawling on my legs lasted for a while too. I dont know if this was from the sunburn, but it is the only thing I can think that would have caused this. I got heat rash on my legs and a bit on my arms but my torso was covered and did not get sunburnt from the sun that I know of and it has isn t affected by heat rash. Thank you and sorry about the lack of information, Bridget.