Oh, very cool! I would be really interested to see what happens next--what do these aliens consider currency?

And I agree with everyone else, don't be so hard on yourself ;) It is a lot of telling, true, but that's the kind of story it is--I don't think the "show, don't tell" rule applies to flash fiction as much as longer kinds. It would be a very different story if it focused in on a character or characters in order to do more showing. (Not that I think it would be bad, but this way it works well for the kind of story it is.)