When you're ill, why do you feel worse at night?

I feel like a hitherto undiscovered cranial dairy has made some kind of massive breakthrough regarding the efficiency of cheese manufacture and is producing more than my head can contain. As a result it has built up and is in the process of being forced out of all the major orifices associated with my noggin. Tripled with this are a general fog around my senses and a nasty cough that invariably results in chewable, bitesized but textually objectional nuggets of mucous.

Yes; I have man-flu.

The thing is I've had man-flu all day. And yesterday. And on Friday. During the evenings and night times I have felt pretty much as described above, but during the day I have been a little more able to function close to what is, for me, normality. Half an hour or so ago, as I was catching some of the runnier* produce of my skull-dairy, I started to wonder why this was, and had a quick search.

As always, what follows is the result of a few minutes' research on a subject I know little to nothing about. Please don't use it to make life-changing choices or as evidence in a heated, medically-themed debate. If anyone knows better, please comment!

I came across two ideas that make a little bit of sense to me. They are:

1. When you're lying down everything** redistributes itself around your body. For example, excess cheese manufactured in your head won't necessarily be fairly shared amongst your body parts by the workings of gravity. Instead, it just stays where it is until the forces of pressure conspire to force it out of your nostrils.

Except that I'm not currently lying down, and I still feel like someone's kneeling on my throat whilst forcefully emptying can after can of squirty-cream into my nostrils. Here's no. 2:

2. Your body is not a static thing. Throughout the day, various cycles are played out. Some of these involve different levels of hormones and other chemicals being manufactured, distributed, used up, excreted, ingested or defibrillated***.

It makes sense, to me, that different levels of different chemicals at different times should make you feel... different. It's not too much of a leap in the thought process to think that maybe that could have an effect on the way your body deals with having a cold (sorry; man-flu), or on the way that you perceive your symptoms.

Convincing, no? But while I was surfing through a number of responses to similarly titled questions, I came up with an idea of my own (at least, I think it's my own. I didn't wilfully plagiarise it from anywhere). I don't think this is a definitive answer; far from it. If it has any place in answering this question at all it's as one of many possible factors that all contribute to the same effect:

3. During the day you're generally busier than you are at night time****. For example, on Friday I was at work teaching all day. On Saturday I was wrestling my way through Lincoln's Christmas market for most of the day, and today I visited one my other-half's grandparents, visited one of my own grandparents' graves, and went for a birthday lunch with yet another. In the evenings I have generally loafed a bit; my attention has been allowed to wander from grappling with people who think maths is the worst thing in the world, people who think it's acceptable to blow fag-smoke in your face and people who can't quite remember where they live (respectively), to dwelling on my own miserable blocked-yet-leaky situation.

My point is that feeling crapper in the evenings than during the day may be due in part (large or otherwise) to the fact that you simply have fewer resources available for thinking about it when you're busy.

I could, of course, be completely wrong.

* Particularly mature Camembert or Brie? Or just some forgotten Dairylea, perhaps.

** Well, not actually everything. Your feet, for example, don't end up near your ears. Unless you're into that kind of thing.

*** Yes, yes, I know. Just checking that you're reading.

**** This obviously doesn't apply to night-shift workers.