If it's really only "flu", do not need to take any drugs. 現今沒有任何藥物可治療感冒, because no drugs can kill the flu virus. The drugs that doctors give people only help them feel better, cannot help to cure it. The only way to cure it is people's 免疫系統.
Rest more is important!
Or you can still see the doctor and ask advice. It's mainly try to see if there's some other problems. If he gives you drugs, ask them what's the purposes of each drug and you decide yourself if you will take them.
It's good to avoid unnecessary drugs and so can avoid unnecessary worries.