i have a pimple on left side of my chin. But its small, its kinda painful when I woke up this morning my left side of lower lip is swollen and its increasing my headache so badly.... I think that pimple is mainly the cause of swollen lip but on the other hand i think that pimple is'nt big enough to cause this swollen lip... the pimple was forming from last two days and now, today when i woke up, i found this overnight left side of lower lip swollen.