I think my 2004 Mazda 6 3.0's automatic transmission is having problems, what are these symptoms of?

With the car warned up and running cheak the transmission dip stick you dip stick and see if it had fluid. It does sound like a transmission problem. Try walking for a day and then you might understand the importance of taking care of your car, the girls......well if your car brakes they will just ride with some other guy. Quit showing off.