No cure so you gotta rest. Nose is stuffed so you gotta mouth breathe. Throat is dry from mouth breathing. Dry throat makes it painful to swallow. Pain keeps you from sleeping and recovering. Lack of sleep leads to worse symptoms like piercing headaches. Need to rest to get rid of the headaches. Headache and swallowing is too painful to rest properly. Lack of rest perpetuates headaches, nose congestion, dry throat, painful swallowing.
What is this BS
There is a difference between vitamins and food. Food has nutrition: not just vitamins but calories, fiber, and such. Vitamins mostly make your pee expensive as your body has to work to get rid of the excess to keep the right balance.
sometimes vitamins are needed - see your doctor for advice not internet comments. without medical advice vitamens are wasting money
you seem to be talking about supplements, not vitamins. Fruit is decidedly not expensive unless you live on the mcmurdo antarctic research station.
People talking about vitamins universially mean suppliments. Whole foods are better, but people talk about eating healty then (also meaningless but potentially better)