X Ray reults show Right Basal Patchy Linear Shadow

Hi, My issue started almost 5 weeks ago with a flue and fever which lasted 24 hours however i was left with a sharp pain just above my left temple and blocked ears and back of my head going down the neck pressurized. this lasted for two weeks and then developed a dry cough which lasted for a week at this point i am feeling very faint dizzy and sick went to 4 different doctors all of whom told me there was nothing wrong with me it is a flue give it another 3 weeks it will go away. during the fourth week the pressure developed in my chest area as well with slight pains to the left and upper back due to this i developed breathing difficulty i will suddenly get the erg to take deep breath and start breathing fast i requested a chest x ray on my last visit and after visiting hospital the results have come back with  "right basal patchy linear shadow". the doctor called me in to pick up medicine "CO-amoxiclav 500/125 mg tablets which contains penicillin. this is a 1 week course and i have been told to go back for a another x-ray in 4 to 6 weeks post treatment. I didn't have the courage to ask the doctor what it was? but i really need to know as i am worried and scared to death it is cancer. i have never been so scared in my life and i need to know if it is what i am dreading. i am 30 years old and a smoker for 12/ 13 years however i have quit since my x ray results which is probably pointless as it may be too late. please please please can some one help. you will be making a world of difference to me. Thank you. bless