Yesterday when I was driving my car, I turned the heat on as usual and the whole inside of my car and dash board started to make a loud vibrating sound and wouldn't stop unless I turned the heat off... anyone know what this could be?

. Ensure that the cooling system is completely full of coolant and that the system has been properly purged of air.

. Verify that the blower motor is not the culprit.

Oh boy, you may not like this, but if this happened after it set overnight, I suspect a mouse found it's way into your blower motor behind your glove box.
Have you ever had any mouse evidence in the past?

Well it must be smelling ripe by now.
Have you had it checked, Nugget?