Back pain on lower left side?

I've had this pain a few times before but it usually disappears on its own within a few hours or overnight. I've had it now for over 24 hours. It's right where my left side love handle is, but it's inside. I can't tell if pushing on the area causes more pain. My stomach hurts occasionally, it's probably just the pain making me nauseous. I don't think I have any other symptoms of a kidney infection, but I'm not sure. I'm well aware that this could simply be a pulled muscle but the pain began out of nowhere, not as I was doing anything strenuous. I'm 16 and usually have minor backpain but this pain makes every slight movement very painful. How long should I wait before seeing a doctor?