I bought a watermelon this morning, brought it home, washed the outside, and left it in my dish rack while I ran some errands. While I was out a small piece of rind blew out and there is now a large pool of slightly grayish liquid on my kitchen counter. I've put the melon in the sink, where it continues to exude a steady stream of foamy liquid, obviously under pressure. It doesn't smell too great either. Does anyone have a clue as to what might be going on?