<human>: Give me the gist of the text in a nutshell

May not be the exact sub for this question but I want to know what im talking about before I complain to the vet. I took my 10 week old puppy to the vet for the first time for his second vaccine shot and they gave him a precautionary medicine for ~~heart~~ worms "because their ~~heart~~ worm test doesnt guarantee my dog doesnt have worms". I told them he also occasionally threw up (a total of about 3 times) It never looked like it had any blood in it or anything so I didnt think it was a big deal but they also gave him a medicine to help with that.  Both of these medicines seem to be expired (Flagyl in a pill form and strongid in a liquid form) They both have a EXP. date from May of this year 05/2014. Its wrighten right on the freaking label so they either think I cant read or im misunderstanding and the medicine is still good. Can anyone educate me on this issue. Is the medicine no good or is it still good?
<bot>: My vet may have given me useless expired medicine and im not sure if im misreading the label or if I just dont know enough about the medicine.