The main function of the thyroid gland is to regulate metabolism---converting oxygen and calories to energy. Thyroid problems can cause damage to major organs such as the heart, but don't normally affect the bladder. Although thyroid problems present many symptoms, reoccurring urinary tract infections isn't one of them. Some thyroid conditions are caused by the immune system attacking the thyroid gland; others are caused by growths on the thyroid gland. In either case, the amount of hormones released by the thyroid gland changes, causing changes in metabolic function. Metabolic changes affect mood, weight, body temperature, energy level and heart function, but not bladder or kidney function. Diseases affect people differently and symptoms can vary from person to person. Reoccurring urinary tract infections---with or without other symptoms---are cause for concern; consult your physician.
Thyroid conditions affect your heart rate and function, and can cause rapid heart rate, atrial fibrillation (heart rhythm disorder) and congestive heart failure. Although dizziness is not listed as a common symptom of thyroid problems, any changes to your heart rate caused by a thyroid problem can cause dizziness. According to the Mayo Clinic, heart conditions caused by thyroid disease are generally reversible once the thyroid condition has been treated.
Thyroid conditions can also cause nervousness, anxiety attacks, sudden weight loss and severe fatigue, all of which could make you feel dizzy. So it's possible to suffer from dizziness while experiencing other symptoms of thyroid problems. If you experience dizziness--with or without other symptoms--report it to your doctor.
All thyroid problems---including thyroid cancer---affect your heart. According to the Mayo Clinic, the most serious complications of thyroid conditions involve the heart.
If symptoms of thyroid disease are ignored and the problem progresses, you can develop thyrotoxic crisis or myxedema. Both conditions are caused by advanced thyroid disease and both conditions---although rare---can cause dizziness. During thyrotoxic crisis, your pulse becomes rapid, you develop a fever, feel delirious and could be dizzy. During myxedema your blood pressure drops, your breathing slows, you become unresponsive and could feel dizzy. Although dizziness alone isn't related to your thyroid, if you suffer from a thyroid condition, dizziness could be related to your thyroid problem.