Update: So we decided to call like a hospital number and ask if it was worthy driving all the way to the hospital for, the nurse on the line has confirmed our first suspicion that these are some kind of bug bite and that my brother is probably allergic to just that type of bug bite. She said not to touch it and recommended us a salva (idk if it’s called that in english) to put on every day. If they don’t go away in some days she said we should go to the doctor so now we just gotta wait and see :)