Don't worry, dude. You probably just got a bite from a bug in the middle of the night or it could also be the result of a pimple. Weird, I know, but that was the answer I got after searching on the web as a result of waking up with the same thing today! Evidently it's quite a common occurance. Ice it inside and out for about 10 minutes and take the ice pack off and give it a rest about every 15 minutes. Too much icing without the 15 minute breaks inbetween could make it worse. Good luck!!

After further research another remedy I found that worked for many with this morning fat lip problem is taking benedryl or some other antihystemine. Some say the fat lip could be result of a food allergy of some sort, eg: too much citrus, msg, food coloring in certain bbq sauces, etc. I know the person who posted this posted it 5 years ago but I put my findings down for anyone else who may need the answers.