1. make a mountain out of a molehill - Verb
2. make a mountain out of a molehill - Phrase
make a mountain out of a molehill (third-person singular simple present makes a mountain out of a molehill, present participle making a mountain out of a molehill, simple past and past participle made a mountain out of a molehill)
(transitive, idiomatic) To treat a problem as greater than it is; to blow something out of proportion; to exaggerate the importance of something trivial.
If you’re stuck in traffic, try not to make a mountain out of a molehill worrying about it too much. You could be making it much worse.