swelled head
US /swɛld hɛd/
UK /swɛld hɛd/

1.
раздутая голова, самомнение
a person who has an exaggerated opinion of their own importance, ability, or attractiveness
:
•
After winning the award, he got a bit of a swelled head.
После получения награды у него немного раздулась голова.
•
Don't let success give you a swelled head.
Не позволяй успеху вскружить тебе голову.