What Causes Red Spots On The Skin?

Question about a non-rash skin irregularity: I only have two isolated red spots on my body. They re on my torso and they only itch when touched, 3/4 of an inch apart from each other. They have a less visible white center now and my son has one similar looking bump on his chin but its much smaller. He has already had the chicken pox and the vaccine, as have I. Just wondering what it could be? I just had my flu shot two days ago but I ve been very tired and have a headache. I blame that one the vaccine but I m not so sure. Thanks.