Brown could be OK, but we would need to see pictures to know for sure. There could be burns, infection, bruises, fungus... but with just a basic color description it is too tough to tell.
well some people say its because he's trying to grab more heat. i think its because too much heat and he's super dry. my cham gets brown when i change the basking light to a higher one.
My chameleon is always brown during the day when he has his hit light on but when he has a low brightness light at night he sleeps in a bush and turns a brighter color until I turn on the bright light does this just mean he is constantly basking it's not exactly very warm at my house.