I'm going to go out on a limb here and remember we cannot diagnose anything. If your breath smells fruity, then you COULD have Ketoacidosis which needs to be treated ASAP.
Diabetes can affect periods. You COULD have it. Does it run in your family? The tiredness and headaches COULD be diabetes.
Here are some symptoms:
Type 2 diabetes: Symptoms - MayoClinic.com
Are you craving sweets?
Do a simple test for me. Pinch your thumb with the nail of your other thumb until the area under the thumb turns white. Remove the pressure. Does the area under the pressed thumb return to red instantly?
Remember, that this is only a guess.