I have mild asthma, and there are times when, if I bend over in the way you describe, I can hear a faint, rapid
ticking noise in my chest
. However, it is not in time with my heartbeat, and it mostly occurs towards the end of a long exhalation. In my case, it seems to be specifically related to airway irritation. I wonder if you are experiencing something related to your bout of pneumonia.
As the doc says, see someone and get it checked out just to be on the safe side.