It mean you not act your age. Having or showing emotional or intellectual development appropriate to someone younger.
Immaturity(;
The hormone that causes sexual immaturity when deficient is the sex hormone. For women especially estrogen deficiency can cause sexual immaturity.
Both are grammatically correct, but for the sake of flow of the sentence immaturity will do.
Immaturity.
immaturity
you will never hit puberty
Insecurity and immaturity.
immature
Immaturity
Time will do it for you. Just relax.
The immaturity of the human brain.
Panty Raider From Here to Immaturity - 2000 VG is rated/received certificates of: USA:M