I suggest making a Sparkpage, and making your fitness and nutrition trackers public; then, you can post in the Fitness and Diet forums, and get individualized help from folks on what you may be doing right and wrong!
Plateaus, though, are generally longer than a few days. Losing 2 lbs in a few days (and gaining it back) is not a plateau; that's normal! Our weight isn't a static number. It's more like a vital sign, like your blood pressure! As fluid in your body shifts, you eat, and you sweat or eat salt, you can have major shifts. Case in point: One day, I weighed myself at my usual time, frst thing in the morning, after my morning constitutional (hah!) and naked: 195. I weighed myself that night: 199. The next after, 201. The day after that, 195.
I did not gain four lbs of fat one day, and two more the day after! I didn't gain or lose any fat. Fat's a long-term process... as you sweat, you can lose 2 lbs or more just from water weight!
The best way to avoid these scale fluctuations is to weigh yourself no more than the recommended once per week. Weigh at the same time, under the same conditions (most people choose first thing in the morning while naked, so they get a truer picture of their weight.) REmember the actual numbers aren't that important... weight doesn't tell you how much muscle vs fat you have, it doesn't tell you how fit you are, nor how far you can run nor how much weight you can lift!
If you go several weeks or more with no change, Sparkpeople has a great series of articles on how to break through a plateau: www.sparkpeople.com/resource/fitness_artic