Thanks for writing to us.
As you had mentioned that your mom is diabetic ,also having a thyroid
problem, & her recent tests are fine. Since your mom has pain over th heart area & left hand i would suggest you to get an Electrocardiogram of your mom. Diabetic patients are at increased risk of having a heart problem so dont ignore the pain in chest.
Anginal pain ( heart pain ) is usually over the heart often described as heaviness in the chest, assocaited by profuse sweating
& often radiating to the left hand, neck. So kindly get a electrocardiogram (ECG) done for your mom.