1989 Ford Taurus Transmission (this question was revised)?

My car is a 1989 Ford Taurus GL with a 3.0L Vulcan V6, not the SHO. It has 92'020 miles on the odometer. It has an Automatic Transmission. When I got home from town today I heard some noises from under the hood, the transmission in particular. When the cars warmed up, it clunks into reverse. And it was also warmed up and I put it into drive and reverse from park, and then from eachother, I heard a very faint,"shhhhhh" kind of a noise, followed by a tick, also kind of quiet. The transmission was rebuilt on September 27th 2002 and it had 76'402 miles on the odometer. And its acting like the transmission has almost a hundred thousand miles on it when it really has less than 20'000 miles on it. I checked the fluid about a month and a half ago, it was a redish color, like an amber, which its supposed to be, but I cant remember how full it was. Im going to go check it. Well I checked it and its amber colored, and it was pretty full, all though the car had been sitting for about 25 minutes and it was all the way warmed up. My mom drove it up until last January, when I got my permit, but I babied the car. When I got my license in October of '09. Im not hard on it, but I have had to floored it a few times, and then the occasional fast take off. But, I'm not reckless. And I wouldnt think that a few hard take offs would make a transmission of less than 20'000 miles clunk and act way ahead of its age. My dad and I are going to take it to a local transmission shop on thursday and get the fluid changed and the transmission checked. Other than the fluid, what else could be causeing all these problems?