So frustrating...

So, I had complications with my postpartum recovery and wasn't able to to start really working out until recently. I'm 7 months postpartum and I'm the heaviest I've ever been in my life. I'm 5'2 and in the 150s right now. I was in the 120's pre-pregnancy. So I have about 20-25lbs to lose. I purchased a digital scale from bally and it is constantly reading my weigh ins differently. For example I was on the scale and it read 154. Then I got off, waited for it to clear, and back on and it read 150. So naturally, I'm now confused. Like which one is it? And I'm just getting discouraged and feel like I'm failing. Getting tired of this crap, and am looking for a better digital scale to help keep me motivated to track my progress and not give up. Any suggestions?