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

1.
subírsele a la cabeza, engreimiento
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.
Después de ganar el premio, se le subió un poco a la cabeza.
•
Don't let success give you a swelled head.
No dejes que el éxito se te suba a la cabeza.