I think best decision for now is wait and when it fall to the bottom buy LTC. Because it will go up very soon!
Actually the whole market is red now because of Bitcoin falling, and I believe that Litecoin is also low for this reason! When BTC will be up again Litecoin will follow, it's been this way in all similary situations!
Inasmuch as bitcoin Price is falling it is clear that it's affecting other currency because BTC Dominance is about 35.4% of total marketcap