There are actually two spots on Bloody Bay you can walk to. Both are called the Office of Nature (the group of guys split up and both using the name). Both rustic, but you can get a beer, or rum.
If you want a store, The PetCom gas station is your best bet if you don't want to go that far. They have beer, rum cream, wine, and lots of snacks. Its a good size so lots there for your room.
Otherwise, you need to come into Negril a little further to get to any true bars...off the top of my head...Cosmo's is one of the first places, then lots more as you head down the road.
I do suggest you take an afternoon to walk the beach in Negril proper. You can take a taxi to Sunbeach...great bar and you can start walking the beach in either direction from there and stop along the way...one of my favourite pastimes!
