Your car, the Escort, and the two Mercury twins are what we have long referred to as "killer cars" because of the huge number of part failures leading to loss of control and crashes. You're experiencing one of the signs that something is about to break. The moving steering wheel indicates a steering or suspension part is worn or loose and allowing the wheel alignment to change.
You have enough problems already too with the alignment. If you look at the front wheels from in front of the car you will see they are tipped WAY out on top. That was done to trick people into buying them. They ride much smoother than other car brands because they scrub along on the outer edges of the tires. What the salesmen didn't want you to know is you were lucky to get 15,000 miles on the pair of tires. To make it even worse, Ford couldn't be bothered to build in alignment adjustments to allow us to try to correct their poor design. Once any worn parts are replaced, the car will still need an alignment to set the direction the wheels are steering to match the position of the steering wheel, but that's all that can be done. If the car pulls to one side, too bad. Ford didn't care about that.
You need to have the steering and suspension systems inspected immediately at a tire and alignment shop. They will have ball joints and tie rod ends in stock because they sell so many of them. When I worked at a mass merchandiser's repair shop in the '80s we got a shipment in every Wednesday that included 40 tie rod ends for Escorts and Tempos, and by every Saturday we were sold out and ordering them from local parts stores. A lot of those cars came in on tow trucks, at least those that didn't skid into a tree or oncoming traffic.