Buzzing Water Pump

This morning I visited our 560 in my storage shed and noticed a buzzing noise. I discovered that the water pump switch had been left on, goodness knows for how long. There is water in the tank, shore power is connected, and the battery meter shows good voltage. The faucet has not been dripping, the sink is dry. I opened the faucet and got water as normal and when I turned off the water, the pump stopped, no more noise.

The buzzing was not there a couple of days ago. Has anyone else experienced this? Should I worry that there may be after effects?