is this some kind of allergy what can be done on this regard?
To be safe, I would encourage you to arrange a doctor visit for your daughter. There are so many things that can cause red spots and rashes in children. Certainly allergies can be one cause, but so can infectious diseases like measles and chicken pox.
Your doctor needs to examine the spots and take a medical history to make the right diagnosis. Anything you can tell him/her about what your daughter was doing before you noticed the red spots or any other symptoms she may be having would be helpful in making a diagnosis.
To your health,