Hey Chloe,
You sound like your at the prime age to have Glandular fever. It's extremely common, and with the list of symptoms you gave, it is highly likely that you've had the virus in you system within the last month or so.
I had it during my final exams (around october last year) and my doctor put it down to the fac that I was working myself into the ground, and my immune system was really low....It's also quite commonly known as the "kissing disease" because its pretty easy to catch from other people - through saliva, sneezing etc.
You could ask your doctor to run a blood test - the antibody/hetrophile will show up indicating that you've been exposed. The good news for most people is that once you get it, you'll never get it again - unless your me, and theres something wonderfully wrong with your blood being incapable of producing the antibodies!
If this is what you have got, the best possible way to get over it is rest....if you're body is telling you that your tired, do as it asks....otherwise it'll drag on forever. The tiredness and flu like symptoms last 4-6 weeks....and because it is so common, and such a nusence your department of education would generally allow special provisions for this condition. In my case, I was allowed to ask for more marks in my final exams as my work was deemed not up to my usual standards...
Hope some of this helped....I understand looking things up on the internet which have a million different symptoms can actually be quite scary. I had similar ones the last time I went to the dr, yet I was under the impression that I couldn't get glandular fever again - and so was my dr, so both he and I were freaking out that it was something a little more serious. I think its good to finally know that that is all it is, and even better that I know I will survive my uni exams next week!
Take Care
Anna