Well, this would be a good time to figure out how to make and use a fire drill, wouldn't it? Without a signal fire, you may be there for a long time.

You have nothing to carry water in, except a thin, cheap plastic bag, and nothing to make a simple still to make drinking water. All you have for rainwater collection is the raft, so you'd better hope it rains a lot. (And you'd better drag it far from the beach and weigh it down with rocks.) If you can't find a source of fresh water (and there may not be any on a small island, as this is not a Hollywood island), you may be in deep doodoo if you can't depend on rain.

And if you can't find or make water, there's no point in wasting your soon-to-dwindle energy on finding food.

I would say that your failure to plan better has landed you in a very tight spot, and you're probably going to have to depend on someone else pulling you out of it.

Sue