I respect that with the power of language, we don't necessarily need to capitalise anything, because a description of how a character is speaking is more powerful.

Take my example:

> 
> The hooded man took another hard right through a thin gap between two
> stalls, forcing Rett to speed up again. With the man out of sight, he
> sped up, half in desperation, half in fear of losing him permanently.
> 
> 
> “Watch it!” a man cried as Rett pushed him out of his way.
> 
> 
> He bumped into a woman as he shoved past, spilling the contents of her bag onto
> the ground.
> 
> 
> "Sorry, ma’am!” Rett shouted back, without stopping to help. He wove his way through and between more shoppers, and quickly took the same right turn that the man did. He ground to a halt when he realised that the man was gone.
> 
> 
> His breathing quickened. “DAMN it!”
> 
> 
> 

I've already got Rett shouting back toward the woman after spilling her bag, but his final words are a curse. A different type of shouting; a real exclamation.

What should I do? Is capitalising here okay, or should I return it to normal case and give explanation?