My 3 month old gnaws on her fist constantly. does it always mean she's hungry? also, her fist is getting rashy?

its completely normal. She has found her hands which are now the most fascinating things in the world! It doesn't mean shes hungry... she is just exploring by putting them in her mouth. A babies mouth is a way they explore... they enjoy feeling different textures in their mouth. As for the rash, I would suggest washing and drying her hands often if they are constantly covered in her saliva. If it doesn't get better, call her pedi :) Hope this helps