When I'm feeling overwhelmed, the worst thing I can do is not think about things and ignore the situation. And this is my default mode of handling it.
Instead, I need to discuss it and actively face it. Writing down a list of things I need to do really, really helps. It stops all the tasks from swirling around in my head and getting tangled with each other. Often, the list is actually very short and doesn't appear at nearly the same magnitude it does in my head.