Light Brown Spots Underneath Tongue. Was A Smoker. No History Of Oral Cancer. What Is It?

I have light brown spots underneath my tongue. Not ON my tongue, UNDERNEATH my tongue. What is the cause of it being underneath my tongue. I use to smoke but not heavily. I only started smoking for 1 1/2 year but it wasn't everyday, i dont anymore though. I drink occasionally. I do not take medicines of any kind right now. With the light brown spots, it looks like a cluster of small veins in one little area. I can determine if its red or brown. The lighting of the flash light gives off different colors from a different angle when looking at it.. What do you think it could be? Ive had the brown spot since i was around 10 years old when i noticed it, so it was one there well before i started smoking last year.I am not 22 years old. But now recently i notice more around it. You cant really see it unless you put the light on it though because it not dark brown, its light brown. The little bubbles you see in the circled area that i circled in the picture, ive had that basically all my life so i'm not worried of that, just the tiny brownness on it and the patch of veins that was never there before... I have no family history of oral cancer neither. Help?