In this context, does podróż mean jus the time actively travelling to somewhere, or does it refer to a whole trip to a destination and back, possibly with many days staying at the destination ("a trip" in colloquial English)? I ask because I'm not sure what this sentence means. Is the speaker saying they're unhappy with how long it's taking to get somewhere, or are they saying that they're unhappy with how long they're spending away from home? (Or, I guess, can it mean both?)
Thanks! I guess „podróż” would be used where context made the sentence's meaning clear. So to say unambiguously that the whole trip is too long, it would be „Nasza wycieczka jest za długa”?
They are almost always interchangeable. There are some situations when only one should be used, but I don't expect such a situation to happen in this course. If one of them (when meaning "too") won't be accepted, ask there.