An old saying:
A cold treated will take 14 days to clear.
A cold left alone will take a fortnight.
However, there are remedies that help you feel better, I use:
one sachet of a paracetamol based hot lemon cold cure powder.
I tbsp honey
shot of single malt whiskey, I like Isle of Islay
Whack it down just before going to bed.
I am not recommending that you should follow me, we are all different, what I use works for me and hasn't killed me, that may not be so for others, use it at your own risk.