It is not uncommon for individuals, including teenagers like your 17-year-old son, to have specific fears and phobias. Fear of spiders (arachnophobia), fear of the dark (nyctophobia), and feeling paranoid after watching horror movies are all relatively common fears and reactions.
These fears can develop at any point in a person's life, and they don't necessarily have to be present from birth. They can emerge due to various factors, such as personal experiences, exposure to certain stimuli (like horror movies), or even learned behaviors from observing others.
It's important to note that fears and phobias are a normal part of human psychology. However, if these fears are significantly interfering with your son's daily life, causing extreme distress, or preventing him from engaging in typical activities, it might be worth considering professional help.
If you're concerned about your son's fears and their impact on his well-being, you could consider reaching out to a mental health professional. They can provide a proper evaluation and offer guidance or strategies to help him cope with and manage these fears in a healthy manner.
Remember that everyone's fears are unique, and it's essential to approach the situation with understanding and support. Encouraging open communication and being there for your son can make a significant difference in how he navigates and deals with his fears.