Home Brew Beer Instructions

My brewing beer at home is flat. How do you rescue?
I bought a kit and while I know it's not an exact science, I followed the instructions the letter. They said to leave for not less than two weeks and should be ready. It has now been over 5 weeks. I put my first pint a couple of days ago and was totally flat. It's just a game of 10 liters and has been stored at room temperature of 18-22 degrees Celsius temperature. Now it's Saturday night and a drinking session is scheduled for Monday afternoon so any quick fixes would be helpful! Thank you very much. Just to clarify it was a 'kit just add water. I have a bottle of beer. It has a pump to be drunk straight from the barrel. This is the category below and I'm not bitter brew lager and who do not want to be soft, but the slightest hint of a head would be good! http://www.boysstuff.co.uk/product.asp?id=10125 Cheers.
What used as priming agent? Not sure what to suggest the game but when I can brew 5 gallon batches add water to corn sugar boiled to my beer fermented before siphon bottles. Also, how a bottle of beer? Only PET bottles and a screw cap? The beer is always flat when done fermentation and need a priming agent and an air tight seal. It can take up to two weeks in the bottles for proper carbonation to develop. I hope something of this aid, but if not just try some of the websites Home Brew (homebrewtalk.com) for advice.
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