This week's Spanish phrase — ahogarse en un vaso de agua — is explained for us by Eugenia, who teaches on our intensive courses.
If you've got a friend finding something way harder than it really is and saying "No voy a poder" (I just can't do this), Eugenia explains that you might say "¡Anímate! Que te ahogas en un vaso de agua" (Come on! You're — literally — drowning in a glass of water).
"Making a mountain out of a molehill" is probably the nearest equivalent in English.
More useful Spanish phrases in the previous posts in the series.