Why am i so paranoid about everything? what mental issue is this?

Self diagnose = risk: People use terms like paranoid all the time without knowing the criteria for dx. It is risky and most would advise a professional evaluation. In abusive or difficult circumstances, becoming suspicious, guarded and frightened can be understandable even if it is very unpleasant.. Try to find a therapist you can explore this with - if it is an paranoia you can get help, if not you can get help too.

Paranoia: Paranoia is a clinical term to describe a psychotic thought process, please get a psychiatric or psychological eval.