The ego is a funny thing.  It can cause one person to be puffed up, or “full of themself” as you say.  It can cause another to be withdrawn and feel unworthy.  Both are human attributes, for the human is the one with the ego as operations manager.  And if you are not only human, then what are you?  Both human and a soul.  The soul knows no separation from other souls, just role playing.  Ego takes control when it has grabbed your attention enough to lose awareness of your true nature as spirit.  If you are feeling full of yourself or empty, you are caught up in ego’s snare.  To release the trap simply see through the ruse and shed the costume.  Be a free spirit, neither proud nor ashamed, but humbled, which is quite different from the latter … humbled with gratitude for having turned around before becoming completely lost.  You are so very loved.