sick map turtle

Question
Hi my son had a map turtle, at first it was fine, then it wouldn't eat much and it got very lethargic, so we got a heat lamp and a UVB lamp as our local pet shop told us, it seemed to pick up a little then we found it upside down in its tank, so I put it on its rock and it looked like it was gasping for air, later that day it died,He wants to get another one but we are worried it may do the same.Any suggestions please

Answer
Hi Im sorry for your loss. Can you tell me please about the set up and what bulbs you are using?
Id like to assist you with the correct info to be able to assist in keeping your future shelled friend healthy.
As far as the gasping, he could have been to hot or had pneumonia.