Patrick wakes up one morning to find that he has developed an enormous pimple right on the end of his nose. all throughout the school day he is absolutely sure that everyone is staring at the blemish, when in reality almost nobody cares enough about it to even look. patrick's certainty that he is the focus of others' attention demonstrates

I believe the answer is: imaginary audiences
Imaginary audiences refers to a situation where an individual use their imagination to create audiences that would enthusiastically paying attention and appreciating everything that he/she is doing.
This process is very common to appear during adolescent years when people started to develop the desire to be accepted by a certain social group.