If it really tastes of light vinegar... it probably is... so relax and put it in a corner with plenty of air access to become a delicious honey vinegar. Keep in mind it will develop a MOV (mother) and continue to develop that flavour.
If it's a mischaracterised acid flavour you should leave it and revisit your brew after a month or two, then look at stabilising, backsweetening and balancing the acid.
To be honest though, if it tastes like ****, just cut it away and improve your process. Learning to make mead is hard as there are less great resources available than beer. I've also noticed people's opinion on what "good" is, Varies greatly. I learnt through a few online resources and a lot of trial and error.