Hi Dawnma,
I have had a few weeks where the scale didn't change as well. Is it that time of the month? That can effect weight with bloating.
You said you've changed up your exercise. What do you do? I used to walk a lot, which I still do, and I love it, but when I added some hard calisthenics (30 Day Shred, Kickboxing) I saw a change in my body that was beyond the scale.
Do your clothes feel different? Can you do physical things you couldn't do before? That is a good thing to look at that goes beyond the scale. Don't let those little numbers freak you out.
I had a few weeks with no change in the scale, I was wondering what was up. Then after a few weeks of that, I stepped on to see a 6 pound loss. So who knows, maybe I was holding water, maybe the harder workouts caused my muscles to hold on to water, I don't know- but it paid off.
Be encouraged- you're still doing what you know works, judging from your past results. Just keep going.