Bump on lower lip... So scared

About a month ago I noticed a bump inside my lower bottom lip... I thought I might have bitten it and would go away... But it hasn't... It's not getting any bigger and there are days I feel as if it's getting smaller until I start messing with it.. It's absolutely invisible I can just feel it with my tongue or finger it's hard and scaring me since I am a smoker and drinker.. I'm only 22 and have read online that that's pretty young for cancer.. But I'm a serious hypochondriac... Does anyone have any idea what this could be.. Please help!!!!