Either way would be acceptable, really. You could let it go for another week, and it will clear on its own. Or, you could do the water change, and it would be gone immediately.
I would suggest that it is probably NOT the gravel that's causing the cloudiness. It can, but for a matter of hours not days.
I would suggest that it is probably NOT the gravel that's causing the cloudiness. It can, but for a matter of hours not days.