Sick again

I am sick again. I am not sure why I get sick so often after I came to Australia. What's wrong with my immune system? I think I got sick almost every month.

I started to feel sharp headache and body ache and sore throat. The pain is so sharp that I almost couldn't control myself not to scream. I have to eat pain killer to reduce it and wake up every morning due to the pain. I started to have fever since Friday and sneeze since yesterday. God, I feel so bad now, headache, body ache, fever, sore throat, and running nose.