I'm 15 And I have a small blister like bump in the corner of my mouth. it's small and it doesn't spread. I've tried to pop it but nothing but a water like liquid comes out and the blister fills again. it's not a whole ton of gashing liquid just a very extremely small amount. It's also not noticeable and it's a tad sore since I've been messing with it. can anyone tell me exactly what it is. A friend told me it was herpes but I've only been kissing my boyfriend lately and he's a virgin and I'm his first reap relationship . he also doesn't have the same sore I do. it just appeared recently since the cold weather made my lips super chap and the corner of my mouth started to get dry along with my lips. I hope it's nothing serious.