Hi, Sam
First, are you sure it's just a cold? Several other conditions (including Lyme disease) start with flu-like symptoms, so if you've been anywhere you might have been exposed to tick or other bites, go see your GP.
If you're sure it is a cold, the best you can do is try to alleviate the symptoms until it has run it's course. My personal favourite recipe is:
2 teaspoons of clear honey
2 teaspoons of pure lemon juice
2 teaspoons of dark rum (Woods 100 works best for me)
Make up to a large mugful with boiling water, and drink as soon as cool enough.
Hope this helps, and you recover soon.
Alan
No man knows true happiness until he's married......but then it's too late!
Proud member of the Greater Manchester Bushcraft Group