Why am i tired all the time?

Need context: With such a vague symptom, it is impossible to give a good answer unless we know the context what other symptoms you may be having.

Non specific: The differential diagnoses or possible answers are varied. Given your age and sex the possibilities include perimenopausally related, anemia, to metabolic conditions such as thyroid conditions or diabetes, or vitamin d deficiency. Infections are common such as a simple bladder infections which are treatable. A more thorough history and exam is necessary, possibly even tests.

Need examined: Your dr needs to do a thorough exam and some bloodwork to see if there is an endocrinological (like thyroid) or cardiac or other reason for this. In mean time, try to be sure to get reliable, quality sleep, 7-9 hours per night and can take short naps mid-day if still tired. Try going for short walk or other physical activity to recharge yourself (not wipe out).