its weird, then during the day ill start day dreaming and this happens again

heres the dream-
ok so i goto the lake
we stop the boat and go swimming, which we also do in real life when ever we goto the lake
im just swmiming and kinda floating with a life jacket and somethin grabs my hand, and i jerk back then put it back
it gives me something and then goes away, i dont see it, but i hear a voice it says never tell where u got this
so im like well alright and i lift my hand outa the water, its a shell with a small stone or coin around it, i drew it and ill post a picture
its too blurry to tell if its a coin or gem, but it has my initial carved in it
then it shoes me wearing it

the neclace is about 2 inches long

http://i34.tinypic.com/211xnc.jpg

what is this? a messege from a water spirit? a premonition? please help!