Okay so, I finally had to take a break today. I have no idea why... I've been smoking the same tobacco, out of the same pipes, with the same method of packing, but for some reason I've been getting bit lately. Which is weird, because in the three years I've been smoking a pipe, I've never once experienced tongue bite. It's not a horrible bite, just a slight pinching, stinging, burning sensation. I know it's not tongue burn (Well, maybe it is. Not short-term tongue burn from an exceptionally hot bowl though, but long-term burn from smoking too much, thus making my tongue susceptible to discomfort from even low temperatures.). Who knows, but yeah... felt like I should give my tongue a rest.
PS. It could be that I cut back on my cigarette intake significantly in the last few weeks/month. I went from 3/4 to a pack per day, to approximately five cigarettes per day.