My daughter got her first Dtap at 2 months and her second around 3 years. When she got her second dtap, she had a crazy rash. I even took pictures of it. There was this huge red slightly raised circle around the injection site. If I remember correctly, that went away and then a new rash showed up that was a large ring around where the previous rash had been. It was strange and it took a while to clear up, but she was otherwise fine and other than feeling a bit sore, she had no other symptoms. Just keep an eye on it and call your doctor if there is anything that worries you.