Whats this white line by where my blister is?

Ok well, my friend and i were sitting on his porch, and he burnt me with his cigarette well i let it go, there was just a little mark, when i woke up there was a really big watter blister that was clear but turned yellow later on in the day, I was not going to pop it but did anyway, And there is this white line that kind of comes and goes, it stars at my blister and makes its way up my arm just by a littlebit, What could this be, thanks to all who answers, and i dont really want to go to the doctors for a blister