So I'm 18 and I've had this cough with phlegm for about 6 months now, which a set of normal antibiotics didn't do anything for. I also had this cough last year for about 3 months as well. This time I've got lower back pain, consistent headaches, night sweats and extreme tiredness. I've never smoked but I've been sent for an X ray and a blood test and am waiting on the results. Are there any other likely illnesses or should I be worried?