Answer:
I am heavy forward but backward I'm not.
2 in a corner 1 in a room 0 in a house but 1 in a shelter.
If I drink, I die. If I eat, I am fine. What am I?
I am the kind of dog that chases anything red. What am I?
I fly yet I have no wings. I cry yet I have no eyes. Darkness follows me. Lower light I never see.
No matter how little or how much you use me, you change me every month.