I've been getting a small cluster of tiny bumps on my bottom lip for a few years now. They usually come every other month, a few days before my period. They usually end once my period actually starts. The bumps don't hurt, or itch, but I can feel them when I rub my lips together or rub my teeth over them. I have continued using chap-stick while I have the bumps, because the bumps have never spread. At first I thought the bumps were from an allergic reaction to any lip products I was using, so I switched and got all new products. I also thought the were a reaction to the sun, so I used lip products with spf. None of these things have made them go away and now I'm really starting to get worried. Does anyone know what this could be??