2 days ago, I noticed something at the floor of my mouth, under my tongue, its like a pimple(because there's a small white at the top, that's why I thought it's a pimple), about 2mm with fluid inside so I used to play it with my tongue, but today, I noticed that the liquid became a solid ..I don't know what it is. It is painless from the first day that's why I am not bothered about it, but now I'm beginning to get worried about it. The tip now is white and slightly rough when I feel it with my tongue.