Hi im 19 years old, recently one of my upper teeth cause me a slight discomfort, the doctor said all was fine there is no chip, no sensitivity, no cavity, but i have been under lots of stress lately, what should i do?

A few thoughts... if there is no caries or trauma, you may be grinding your teeth or you may have sinus inflammation. Have those potential issues checked.

Stress is one of the main reasons one may clench; front teeth are especially susceptible to grinding and clenching because they are one rooted teeth, teeth with more than one root (like molars) are less susceptible to biting forces. Have a dentist evaluate the need for a mouthguard.