@tanguatlay,
No, that usage is proper. But reflexive pronouns like "myself" are only used when the context requires a certain emphasis on the subject.
If someone asks a direct question, "Are you a native speaker?" it would be unnecessary to add "myself", you could just say "I am not a native speaker." But if someone pointed out differences in pronunciation among a group of people it would be quite natural to say "I am not a native speaker myself."
Just make sure never to use "myself" as the subject.