A swollen face is definetely caused by thyroid. Your thyroid problems are probably the worst. I would look into the things I posted you first, is scientifically proven that they boost the thyroid function. I will take them when my leaky gut and AF are better.
Fatigue after eating could be a sign of gut issues but is hard to know without more symptoms or tests. How are stools and skin often serves as a diagnosis for gut though.