Is it normal to be afraid of jets and planes?

This has been going on for a while, I don't really remember how long, about 6 months maybe. I get so freaked out when I see Jets or planes flying overhead. I keep thinking they're going to drop nuclear bombs. I've been having non-stop dreams about them, and it won't stop, actually it's getting worse, so much to the point of me shivering and wanting to run every time I hear or see a plane, I want to know if it's normal to have such a fear.