I think I have the beginning of the flu. What are the main symptoms?

An overwhelming desire to crochet cushion covers whilst singing 'The Eye Of The Tiger' is usually a good indication of the onset of Flu.

Lucyinthesky has it. Add chills in there sometimes.

I had it and it wasn't too bad. The first symptom I noticed was heavy legs like it was difficult to put one foot in front of the other. The next thing was the headache really bad but paracetamol eased it. Then the high fever very sudden that it the sure sign. It only lasted about 12 hours but the aches and weakness went on for a few days. During this time my chest started to hurt and the cough came. Went from there into a chest infection. Took two lots of antibiotics to get rid of it. I kept off work for seven days but still felt weak for a couple of weeks after mainly due to chest infection.
I didn't take antivirals because was worried about side effects. Go to doc if chest infection develops after flu. To be honest I have had worse. Just look after yourself.