Getting extremely upset when a parent gets a new pair of glasses represents:

Autism

Explanation:

Autism, also known as autism spectrum disorder (ASD), is a developmental disoder that refers to a large range of conditions associated with challenges of social skills, repetitive behaviors, speech and nonverbal communication.

People with Autism, may often become very upset at minor changes in their environment such as objects, persons, or routines and try to stop any efforts to change their own repetitive behaviors; For example, some autistic behaviour includes reacting with tantrums if a parent wears an unfamiliar or new pair of glasses.

Hence, in this case, getting extremely upset when a parent gets a new pair of glasses represents Autism or Autistic behavior.