About 4 weeks ago i had severe flu, and felt terrible - as i was getting over this i awoke in the middle of rhe night with terrible pains in my chest, in a cold sweat and felt very nauseas. i went to the doctor who said it sounded like my heart, gave me an ecg and said no my heart was fine. all during this period i had terrible headaches that i couldnt get rid of. i finally started to feel better, but still awaken in the middle of the night in a cold sweat with a terrible headache that normal panadol doesnt help, i need to take panadene forte. i feel sort of light headed and just not well, im a bit worried - could it be something serious ?