I restarted my 20mg EOD protocol recently and within the first injection I developed a nasty cough which began hours after the first injection and I had chest congestion and coughing up mucus, each subsequent injection the cough was on the decline and my cough is 95% gone a little more than a week later.
In the beginning the cough was really bad and frightened those around me because of the coronavirus spreading around the globe. I haven't been sick since I was 14 and am 48, no flu, fevers or colds. My brother is the same, he never gets sick. My immune system was able to take care of the cough in short order.
The same cough occured when I first started TRT way back in 2017, but subsided quickly. It's hard to tell if your case reflects mine because it is flu season.