It's important to differentiate between a harmless crush or attraction and a delusion. If someone consistently stares at you or shows interest, it may not necessarily be a delusion on your part to suspect that they might be into you. Sometimes, people do show signs of attraction through body language and consistent attention.
However, if you find yourself interpreting every interaction, even mundane ones, as evidence that the person is romantically interested in you, despite clear indications to the contrary, it could be a sign of a delusion. Delusions are persistent false beliefs that are not grounded in reality and can be a symptom of certain mental health conditions, such as paranoid delusional disorder.
In most cases, it's best to communicate openly and honestly with the person you suspect is interested in you to gain clarity about their intentions. Jumping to conclusions without evidence or misinterpreting innocent actions may lead to misunderstandings or unnecessary emotional distress.
If you find that your thoughts or beliefs about someone's interest in you are causing significant distress or interfering with your daily life, it might be helpful to discuss your feelings with a mental health professional. They can provide support, help you understand your thought patterns better, and offer guidance on managing any anxiety or emotional challenges you may be facing.