Immature
Part of speech: adjective
Definition: Not fully formed or developed, unripe. Childish in behavior.
Example sentence: In the past I would self destruct when it came to love - I was immature, throwing myself into things but now times have changed, I want a relationship where you understand the other person.
Undeveloped
Part of speech: adjective
Definition: not developed or usedlagging behind others, especially in economic or social matters