Some places of employment do get like that where there's inadequate training. Just tossing people in and expect them to swim, gracefully at that. Sadly, I do believe inadequate training is a sign of the times. Sometimes we luck out and work alongside someone that has it figured out but most times not. Overworked and underpayed all for the almighty bottom line.
Are the floors concrete? That ails most when being on the feet all day. I personally don't find sneakers of any use on concrete. Especially for multiple hours at a time.
It is good to search now that you are employed. I've known some to have magically discovered a more lucrative and lengthy employment after a short stint, opportunities that only arose after beginning at the cruddy jobs. Guess that I can only give hope?