I pretty sure I am overtraining. Even though I took yesterday off from the gym, today when I did my cardio (at the same level as Monday) my performance was noticably reduced.
My question is...What is the best strategy to use to combat overtraining?
Increase my calories (I'm at 1200 plus 1 milk and 1 protein--which is around 1400)?
Decrease the intensity of my workouts?
Decrease the number of workouts? If so, which ones: the cardio or the weight lifting (I do them on alternate days--cardio 2-4 times per week, lifting 2 times per week)?
Any advice? Thanks.

Overtraining really isn't about calories, it's about not getting enough recovery time for the amount of work you do. Do you know what your resting heart rate was BEFORE you started feeling this way? If so, try taking your pulse immediately after you wake up, before you get up or even stir around in the bed. Do this for a few days in a row. If your heart rate tends to be higher than you know your resting heart rate usually is, then you may be over trained. The only real cure is rest. So, I would probably take a few days off, until my resting heartrate returned to normal, then ease back.
P.S. I picked up this info as a semi-regular reader of Kathy Smith's bulletin board on iVillage.

I suspect that what you mean by "over-training" is that you suspect you are working too hard, too frequently and too long. It sounds like you *might* be overtraining, but it's hard to say when you don't give any information about duration and intensity. I don't think you are working out to frequently, because I work out virtually every day for an hour or more, and I don't feel at all overtrained, and I don't have any symptoms of overtraining--unless I push too hard. If you are working out at too high an intensity, you may be affecting your progress more than actually overtraining.
It's easy to work out at too high a heart rate, and force yourself into working out anaerobically, even though you are doing what is technically an aerobic exercise. When you work out (running, walking, biking, swimming, etc.) for an extended period of time anaerobically, you are working out at too high a heart rate for significant conditioning to occur.
This also can cause your heart rate to be elevated quicker the next time you work out.
If you are working out pretty hard all the way through your workout, you might want to try working out at a much lower heart rate for most of your workout, and have several intervals lasting 1-3 minutes where you push yourself.