There is 60k miles on the car, I do not know.

There is 60k miles on the car, I do not know what has already been done to this car because it is my father's. The car will gradually drift from one side to another when going at a fast speed. This happens while driving at all times. It drives unevenly and feels like a tire pressure is much lower than all of the others, but the tire pressure is 35-37 on all. No check engine light. No warning lights. This did not happen all of the time, I go to school downtown and I think a pothole caused the problem. No accidents. I drive this car 35 miles a day Monday-Friday for school. And there are potholes downtown and they are impossible to avoid. I go over them every day at a slow speed. I have gone over one at a high speed maybe twice. Another time the steering wheel shook once back and forth at the same time my front end of the car was shaking back and forth violently and this happened at a slow speed 35 mph-25 mph. The steering wheel once shook when I was stopped as well. Please help thanks. My car is a 2009 Saturn Aura XR.