I am experiencing tongue problems. white thing hanging down bottom of tongue. appeared over night. about the size of a grain of rice?

Salivary stone: What you are describing sounds like a salivary stone. These are calcifications the may occur in the salivary glands or ducts. They may cause blockage of the duct. Sometimes, these pass on their own. Other times, they nee to be treated by a dentist. You can try Sugar-free lemon drops to stimulate the saliva. It may help it push thde stone out of the blockage. If not, visit your dentist.