I have a job that requires me to stand for

Patient: I have a job that requires me to stand for about 7 hours at a time. And I’ve started having knee pain because of it. My knee has started to pop and ache even when I’m not working. It will hurt on the side and on the softer part under my knee cap. Should I be worried? I never had knee pain until I started working. I’m only 18 and I’ve never had any injuries to it.

Doctor: