My 11 Years Old Son Developed Welt Looking Type Rash

My 11 years old son developed welt looking type rash last night and then a few hours later his lips became very swollen and a little swollen around the eyes. We went to the walk in clinic today but they had all pretty much gone. I had shown a picture to the doctor and he said it was hives. Well now it is back and he now has them on his legs which he didn't last night. And these ones on his legs do not look like a welt but more like a pimple and has a whitish ring around them. Is this also hives?