Do you have a fever?
If not, then it is almost certainly not the Flu, and much more likely to be a common cold.
I have felt like that for several days, but it's just a bad cold - no fever.
BTW - A fever is a body temperature that is higher than normal. It is not an illness. It is part of your body's defense against infection.
Common oral measurement of normal human body temperature is 36.8 ±0.7 °C or 98.2 ±1.3 °F ; A fever is usually defined as a temperature in the mouth (oral) at or over 37.5°C (99.5°F). - wikipedia
There are many different Types of fevers - see http://en.wikipedia.org/wiki/Fever
The symptoms of a cold usually resolve after about one week, but can last up to 14 days.
'Megadoses of vitamin C, preparations from echinacea, and zinc gluconate have been studied as treatments for the common cold although none has been approved by the Food and Drug Administration or European Medicines Agency. ' - wikipedia
The US National Institutes of Health (NIH) suggests getting plenty of rest, drinking fluids to maintain hydration, gargling with warm salt water, using cough drops, throat sprays, or over-the-counter pain or cold medicines. Saline nasal drops may help alleviate congestion.