I was recently checking out my snail and found that it had some gravel stuck in its shell. I picked it up to see if I could help and I touched its body, not its shell, and it was hard. The snail has been motionless for a while now and I think it may be dead. Am I right or is the bottom part of a snail supposed to be hard? I'm afraid to prod around too much on the snail in case it is still alive and gets injured because of me. TIA.