Congrats!! Yeah, stress plays a part for sure. Also - EAT MORE! Sometimes when you eat too little (ie, one meal a day), your body hangs onto it for dear life in starvation mode. You can find calculators online that will tell you what your specific caloric needs are (your resting calorie burn and also one based on your activity levels, which at 14k steps/day, is pretty high), rather than the generic "2000 cals/day" model. If you are much below that, or at all below your resting number, you're not going to lose weight. It sounds counterintuitive but I've seen it happen many times (as a personal trainer).
But that is awesome about the shirt!! That's the best way to measure, tbh. How your clothes fit tells you more than the number on the scale, which doesn't reflect muscle mass vs. fat mass or water retention and such. So you're doing great!!