Talk to Gynecologist on Period Flow

Just been noticing that period flow has been frequently decrease .. Earlier had normal 5 day to 7 days with first 3 days normal flow but now from three four months it had been reduced to only 2 days with light flow and than just spotting... Though period are on exact time but just the flow is minimal than usual... What might be the reason... Is that anything to worry about... Other than No medical condition ... Unmarried , 25 age , weight 53 height 5 4"