Left knee hurts, clicks and grinds. happening for years, stairs and chairs are challenge, and road trips. only 19, confused about issue and what to do?

Further work up: You deserve further work up. If you've not had a doc look at your knee, that's where you need to start. A through history and physical needs to be the first step. Xray or MRI may be considered based on the initial assessment.

Need orthopedic eval: Needs orthopedic evaluation. Could be simple instabiltity, but more likely an intrinsic knee problem.