My mom had graves disease...what are some symptoms of it because I've had a 100 lb weight loss in the past year?
Symptoms are variable, but hyperthyroidism often causes weight loss despite normal or increased appetite, heat intolerance, increased perspiration, feeling jittery, fast heart rate, palpitations, and other. If the weight loss was unintentional then you definitely need a thorough medical evaluation.
In any case, it might be reasonable to check your thryoid function tests now. See your doctor!