Cavity or just a pit in my tooth?

So, like the title says—I’ve got these weird little grooves running down the bottom of my two front teeth. It’s right where I bite down. I brush like crazy, nothing ever hurts, and they look perfectly straight, but this indentation is driving me nuts. Finally booked an appointment, but I’m stuck waiting a whole month... ugh. Anyone know if this is actually normal or am I just freaking out for nothing? I'd really appreciate some insight.