I need help! What is this???

Okay, so I picked Cade up at Daycare tonight and immediately noticed some red marks on one of his arms. Initially it had white marks in the middle with swollen red skin around it. There were a group of them so I thought he had gotten bit by a bug or something. I showed a couple employees there and one person suggested I keep an eye on it because it kind of looked like a circular pattern that might be ringworm of some sort. I thought great. So we came on home.

Then when I pulled Cade out of his car seat I noticed more red marks on one of his legs. I'm attaching those pictures here. Let me know what you think they are. Do you think they are just child bites, bug bites, ringroom or what??? I'm confused and thought what better way than to ask some other moms!

Also keep in mind that Cade's antbiotic says "may cause sun sensitivity". Does that have anything to do with this possibly? Okay, gotta go get this boy to bed. Let me know what you think!