My 3-1/2 Year Old Son Has A Swollen And Bruised

My 3-1/2 year old son has a swollen and bruised ear. There is a one in red line on the top of the ear which originally I thought was a scratch but now I can't tell if the red line is under the skin. It is very swollen and black and blue, and tender to the touch. Can attach pics if needed. He has an appointment with pediatrician tomorrow but wondered if with the red line if I should take him to emergency care tonight.