Hello There. My 9 Month Old Stood Up On The

Hello there. My 9 month old stood up on the tv unit yesterday, fell an and hit under his eye. Not sure if it was the eye it's self, but under the eye had a split and his eyelid has a bad scratch. Along with a thick mark going down his face due to dragging while falling.
Today it's come up darkening, and he's had dirreah four times now. He's also been crying most of the day & waiting to be in arms constantly. He's nappy rash is making him scream because of the dirreah. Also off his food. Will he need to see a doctor? And does the dirreah have anything to do with hitting his head? Thank you