This morning, I woke up, took a swig of water, and as I was swallowing it, I felt something jagged and solid hit my tongue. I spit it out into my hand. It was one of my second premolars (second bicuspids).

The broken piece is my normal tooth color on its exterior, but on the interior, there are dark black skids.

On the remaining part of the broken tooth that's still in my mouth, the outermost enamel is missing, but the inside of the tooth (the dentin, which also has a black skid on it) is still intact. It isn't tender or in pain, but when I touch it, it is a little softer than the enamel. The other half of the enamel is still intact, too.

I brush my teeth 2-3 times a day and floss twice everyday. I'm not sure what's happening to me.