Hi My 3 Year Old Son Has Just Said His

Hi my 3 year old son has just said his neck is sore there is a soft lump between his ears and shoulder but towards the back of his nick it is not his glands as I have seen swollen glands a million times its mire behind the glands towards back ov the neck.. He has recently had some sort ov rash up to his knees on both legs it now looks like a bit ov dry skin but in patches..and also now has bit ov a cold runny nose ect...please advise thank you