Do not drive the car. Continuing to drive with low oil pressure can lead to a seized engine. You need to have the oil pressure checked immediately. Possible causes include:
* Low oil level: Check your oil level immediately. If it's low, add oil (the correct type and amount specified in your owner's manual) and check again. However, low oil is just a symptom; you still need to find out *why* it's low.
* Oil pump failure: The oil pump might be failing to circulate oil properly.
* Worn or damaged bearings in the engine or turbo: This could be causing oil leaks and low pressure.
* Clogged oil filter or oil passages: Restricted oil flow will reduce pressure.
The whining from the turbo is likely a result of the low oil pressure damaging the turbocharger bearings.
Immediate actions:
1. Turn off the engine immediately.
2. Have the car towed to a mechanic. Do not attempt to drive it.
3. Get the oil pressure checked. This requires a gauge that's temporarily connected to your oil system.
Ignoring this problem will likely lead to far more expensive repairs, potentially including a completely rebuilt or replaced engine.