I have a rash on my lower stomach (all across my lower stomach) and sometimes it gets itchy but when I scratch it, it hurts also its a bit red and inflamed. I heard it could be a heat rash although it's winter where I am and it could also be from my stomach being a bit hefty however I'm 15 and I'm average weight for my age, and my stomach is quite flat (not hefty whatsoever) so I don't think it could be that. Please help!