My vagina is not really that itchy but i used a glove of garlic overnight. how long should i continue it to treat yeast?

Garlic won't work: If you keep using garlic and nothing else, you may have to treat it forever: garlic won't cure yeast of anything else. And it has awfully strong chemicals to use in the vagina. If you're certain you have a vaginal yeast infection, use a proper treatment like an "azole" cream, available over the counter (miconazole, clotrimazole, etc). See your doctor for diagnosis it the cause is uncertain.