Can a person ve a longterm virul infection of the lungs/throat, if so, how it can be detected-cant give a sputum sample antibiotic don't help. Xray was ok?

See your doctor. Problems like these can only be correctly handled by your doctor in person. He/she needs to listen to you, perform an examination and possibly run labs or other tests. That's the only way he/she can find out what's going on and what to do about it.