My left eye keeps watering and burning. My nose runs but sometimes it's stuffed up, and my throat hurts at times. What's going on with me?

Unclear. If your eye is constantly tearing, there is something amiss! maybe inflammation or infection. If your eye, nose and throat on the same side of your face are bothering you, please see your doctor as this is not normal. Start with either an ophthalmologist (eye doctor) or ENT doctor (ear, nose and throat). Feel better.
Dry eyes. Sounds like you have dry eyes. The eye gets dry causing the burning and reflex tearing. This drains to the back of the nose ant throat through the tear drainage system of the eye. Not sure why nose is getting stuffed up or the throat hurts. Unless you have a viral syndrome affecting the upper respiratory (nose, sinus, throat) and affecting the eyes.