1999 Ford Expedition (E.B. Edit.) -Loud Grinding / Crunching noise in first gear

[UnluckyDucky]

I have a 1999 Ford Expedition (E.B. Edition) and I am having some kind of problem with the transmission.
I was driving along one day (about a month ago) and I came to a stop stop-sign... When I went to take off, the engine revved higher than usual and then jerked forward. After 1st gear, operation seemed normal as there seemed to be no other hesitation in transition to other gears (I took it to 60 mph a couple of times, but there was nothing out of the ordinary). This problem seemed to get progressively worse as I reached about 8 more stop sign / lights on the way home. The more times I stopped, the higher it would rev and the harder it would jerk forward, so I ended up parking it for about a month. Today, like an idiot, I decided to see if it still did the same thing (as though it made itself better or something, right?? But I did miss having it and I suppose I was desperate...). I started it up and backed it down the quarter mile driveway. When I drove forward, there was no hesitation of any kind and it smoothly made it's was up the driveway. I tried it a couple more times... same thing. I then decided to take it around the block (a somewhat country block). There was no problem until I reached the first stop sign which was about a mile and a half away. As the it slowed to a stop, (about 15mph or so) I heard a sound that resembled snapping of a twig. After I made the turn, I began hearing a 'whirring' sound during 1st gear, then normal again after. After the second stop sign, the whirring noise was accompanied by a loud grinding/crunching noise that sounded like metal against metal. Stopped twice more and it got worse and worse. I then noticed that there were new spots in the driveway that were not there prior to my little test drive. I noticed no color in it so I am not positive if it is related or not. There is a burnt looking coloration in the middle of a few spots though, which I find suspicious.
Does anyone have any idea what kind of problem I am looking at here? What could have happened?

Thanks so much!
Unlucky Ducky