Suggest Cure For Swelling & Pain In The Lower Lip

my lower lip swells daily....its worst usually when i wake up in the mornings..and its there anytime of the day!i cant really say how long it lasts for in a day!Sometimes, the swelling decreases by applyin some kind of lipbalm, but sometimes, it doesn't. my lips are always dry. though i overcome the dryness by applying lipbalms, i cant reduce the swelling of my lower lip and also the pain. Especially, there is a dark spot on lower lip which swells more than rest of the part of lower lip.Can you help me with this?
Thank you!