Broken Scale?

I started working out and generally watching my diet in the autumn. I'm not *as* consistent as I first planned but I'm generally pretty good about keeping up on things. Over time I've felt better, my number of reps has gone up and my workout time has gone down (I'm doing HIIT bodyweight workouts) and I've felt more energetic on random things like dashing up the stairs to my 3rd story apartment. While my belly is still a bit more fleshy than I'd like it to be, I can feel abs underneath, my *kitten* and legs look amazing, and I can feel firmer muscles in my arms and shoulders randomly during the day.
I had a scale that measured my weight, body fat and body water. It broke around new years (dropped while cleaning the bathroom and it actually shattered). I've been working out since then and today a new scale arrived in the mail (different brand). I immediately weighed myself, and saw that my weight shot up from 162.4 to 168.6 (I want to get down to 155) and my body fat lept from 14.7 to 23.1 (I want to get down closer to 12).
So my question is, should I suspect the scale of erroring, or is this some weird side effect of all my working out (i.e. gaining more weight from increased muscle muscle mass than lost from fat)? Before I began I was never someone that you would see and think 'overweight' but I was just starting to get to a place where I was a little uncomfortable.