Insecurity

/ˌɪn.sɪˈkjʊr.ɪ.ti/

Slang Meanings

feeling unsure about oneself or one’s position.
She was so insecure that she felt she had to constantly seek validation.
jokingly referring to someone as insecure can mean that they overreact to minor issues.
Stop being so insecure about your outfit; it looks great!