I have had Hashimoto's and have been on Synthroid for many years. Currently my dose is too high and is being scaled back. It takes 8 to 12 weeks before a blood test will determine if a new dose is giving the "correct" lab values. Even then, you might not feel good. A good doc will not go by blood test alone. The point is, it takes time, and it's difficult to lose weight if you are hypothyroid.
I started PB 13 months ago. I already knew I was very sensitive to wheat. When I started, I had no intention of giving up dairy. Forum posters here on MDA repeatedly suggested that ditching dairy was key to weight loss. I gave it a trial (did not give up heavy whipping cream for coffee, though) and the weight did start to go, though slowly. I have lost 22 pounds in a year. My skin rashes went away, as did constant joint pain and stiffness, and eliminated sinus pain and pressure, all as a result of ditching dairy. I walk a lot. My triglycerides are way down, and my cholesterol has come down a bit. You can get lots of good ideas here, but ultimately, the only way to know what works for you is to experiment on yourself. I don't count calories or macros, and I still tend to overeat at times, but its meat, veggies, fruit, and fish.
As God is my witness, I'll never be hungry again.