Hi, My One Year Old Has Developed A Crack/split Across

Hi, my one year old has developed a crack/split across base of penis. He cries every time we try and wipe with nappy change. What can we do? He is poorly too. Fever at night, cough, streaming nose, crying most of night. Temperature went for three weeks but now back, other symptoms seem to be never ending. He's never slept from birth, very unsettled, night terrors, screams every few hours where by we have to feed or rock. Lots of issues, but first is main concern at moment