Mycoplasma Pneumonia. Taken Azithromycin. Infectious?

I waited for ten days before I sought out a reason for my feeling ill. I have mycoplasma pneumonia, have two days of azithromycin to complete. I had the pneumonia shot a year ago, but seems not to have had an effect. For a year now there has been ongoing heavy construction in the neighborhood, small particles of clay dirt can be seen fogging up the atmosphere. Could it be that my exposure during this time has resulted in the mycoplasma pneumonia? I am 79 yrs. should I expect to be infectious long after I am through with the course of antibiotics? Must I stay more or less isolated, that is, stay out of group settings?