Hi, I'm A 50 Year-old Woman. I Had An Acute

Hi, I'm a 50 year-old woman. I had an acute illness at New Year - very sore throat, trouble catching my breath. This developed into a cold and a cough. The cough is still with me - so that's been nearly 3 months now. I've just been to see a doctor, who sent me for a chest X-ray and gave my clarithromycin antibiotics. He mentioned it might be pneumonia. I'm due to fly to Cyprus on Saturday (a five hour flight) and I'm worried now. I've been feeling tired and achey but have just kept going as work as been busy. But I'll be letting my family down if I don't go on holiday and a holiday might help me. I just worry that I might infect other people on the flight and that I'll end up feeling worse. What should I do?