Recently, while brushing my teeth, I noticed that the gum over my left top front tooth was higher that it previously was. I don't usually look at my teeth, as I brush my teeth while in the shower. But, randomly, I took a look at them and noticed that the part of my guns over that tooth was higher. So I went online, and I can't think of anything that fits besides maybe brushing too hard. My teeth aren't red, silken, nor do they bleed, so I don't think it's gingivitis. I don't have the best dental health, but I brush at least once a day for about 4 minutes. This isn't happening anywhere else, and I have no idea what to do. Also, I'm eighteen, not sure if that's relevant or not.