Is it normal to feel no sense of belonging?

I know that I have lovely friends and family and all. But I can't help thinking that I don't really belong to anywhere in this world and always worry that I might lose everything I have or everyone I love someday. I just feel the need to confirm that I belong to somewhere, and it's making not only myself but also those people around me tired. I sometimes, I feel very depressed for some minor reasons(though that time, I feel that it's very serious), and I know that causes of that kind of feeling are usually created within myself, like worrying or thinking too much. Is it normal to be like this?