To think a small problem is a big one; try to make something unimportant seem important. You're not hurt badly, Johnny. Stop trying to make a mountain out of a molehill with crying. Sarah laughed at a mistake Betty made in class, and Betty won't speak to her; Betty is making a mountain out of a molehill.
MAKE A MOUNTAIN OUT OF A MOLEHILL
Meaning of MAKE A MOUNTAIN OUT OF A MOLEHILL in English
American idioms English vocabulary. Английский словарь американских идиом. 2012