Your solid-waste pail is still there. Luckily it did not tip over.
Why would you go to sleep near the waste pail, you wonder, then see a
big rock next to you. It must have fallen from the ceiling of your
waste cave. Which means the cave is going to collapse soon. You run
out of the cave, towards the high rock where you have built your
signal fire. It's gone out, so you re-light it. Is that a ship in
the distance? Or another hallucination? You have to get off of this
island before you lose your mind...
You remember everything. You have just woken up from a dream, or
maybe a hallucination. You have been hallucinating a lot these past
few days. It is perfectly natural to hallucinate in an environment
without any other human beings, but you must try not to go mad.