Hello, i'm 19 years old and very healthy. i noticed this morning 2 streaks on my left ring finger. both are very light however one is darker.

Check with : Your doc to be safe. It could be many things. However, when you see your physician, ask them to make sure it is not a melanoma which shows up as a streak under nail when located at nail bed. This would be rare, but can happen, just rule it our. It may also be something as simple as a birth mark, if no other symptoms, just bring it to attention of your primary next time youre there.