Did you mean hyperthyroidism? If so, the symptoms of hyperthyroidism are
weight loss, heart palpitations (or heart racing sensation), heat intolerance, diarrhea, hair thinning among others. The treatment depends on the cause. For you, it sounds like you take thyroid hormone, so the most likely cause for your symptoms is that your synthroid dose may be too high. The treatment there is to adjust the dose and closely monitor your hormone levels for the right dose.
Estrogen products can interact with thyroid hormone but they usually diminish the effects. However, it is unlikely that the topical cream will interfere with your thyroid hormone. I would encourage you to discuss these concerns with your
endocrinologist when you seen him/her next.
To answer the heading question,
hypothyroidism symptoms include: weight gain,
constipation, dry skin, hair thinning/loss and cold intolerance. the treatment is
thyroid hormone replacement.