There are a few obvious ways to recognize if something bad has happened to your child after vaccination. Most mothers could count every head on their baby’s head, and know right away that something has changed. Eating habits, personality or sleeping patterns—there are any number of things that sometimes feel different after vaccination. You’re purposefully injecting your child with a modified version of a disease, so it’s natural to expect them to feel bad. Sometimes their arm or leg will be swollen and extremely sensitive to touch. This often happens after injections that contain aluminum as their body forms granulomas or nodules around the metal to keep it from reaching somewhere more dangerous.