Your computer crashes the same day your phone breaks.
it never rains but it pours
You were preparing a speech and someone else says everything you planned.
steal my thunder / steal someone's thunder
Your friend cancels plans, but you really wanted to go.
take a rain check
You feel down after a few stressful weeks at work.
in the doldrums
You just got a cold the night before an important event.
under the weather
You finally finish a very hard project at work or school.
weather the storm
You just won a free trip to your dream destination.
on cloud nine
You find out you didn’t get the job you really wanted.
a snowball's chance
You have four exams, two presentations, and a meeting all in one week.
snowed under