It could be either, tbh. I have a female who is... rather cranky. She hisses for no reason quite a bit of the time. Anything that touches her makes her go off, even if it's just her bumping the side of her hide.
Also, I've got a farter, it really isn't pleasant much of the time. He also drinks quite a bit and usually soaks his tub with excess urine at the same time.