Need to change things up somehow!

Yesterday was the third day in a row where I went to the gym motivated only to fall flat on my workout.  I'm not sure why but this week has been very difficult and I need to break through it.  I've had these weeks in the past and I refuse to let this one bring me down.  I'm not sure if I'm overworking myself and starting out a little too fast or what but I need to get back to basics.  I did about 1.5 miles on the treadmill yesterday but my legs were killing me and so  I jumped over to the elliptical for another 15 minutes to make sure I kept my HR at 150 or higher for at least 30 minutes so I felt like I accomplished something.  Scale stayed the same since the beginning of the week which is a bit disheartening seeing as I have been eating less than usual and for the most part healthier meals, very little if any dining out and no fast food and then smaller portion sizing and no snacking.  The only thing I've added is a bagel in the morning for breakfast with a small serving of low fat cream cheese.  I think I'm going to take a day off today, then go tomorrow and Saturday.  I think my body needs it and will maybe get me back on track to success.