Although you have symptoms that are often indicative of hypothyroidism (low thyroid hormones), those symptoms can also be caused by other conditions.
Have you had any thyroid related tests performed? If so, please post any results you might have, along with their corresponding reference ranges from the lab report.
If you haven't had any labs performed yet, talk to your doctor about your symptoms and ask for Free T4, Free T3 (actual thyroid hormones) and TSH, which is a pituitary hormone that indicates thyroid status.
You might also ask for a thyroid ultrasound to determine if you have nodules on your thyroid (very common with hypothyroidism). Thyroid antibody tests would determine if you have Hashimoto's, which is the primary cause of hypothyroidism. Those tests are Thyroid Perxoidase Antibodies (TPOab) and Thyroglobulin Antibodies (TgAb). Both are indicative of Hashimoto's.
There are also vitamin/mineral deficiencies that can cause symptoms and also, often, accompany hypothyroidism. Those include Vitamins B-12 and D deficiency, along with iron deficiency, which is tested via Ferritin, the iron storage hormone. If you've had these tests done, please post their results, as well.