If you’re not sure how to go about submitting a short story to an anthology, Huskyteer has a great article here that goes into what the process is like:
http://adjectivespecies.com/2013/08/30/submissive-roles-writing-for-furry-anthologies/
(And while it’s written with furry anthologies in mind, the process of publishing a short story with a magazine or anthology outside the fandom is pretty much the same. The only thing I would quibble with is that, in my experience, most places don’t want to see a synopsis of a short story in the cover letter; they want the work to speak for itself.)