The air gun thing worked well unless the medic didn't get the nozzle firmly against the skin before he pulled the trigger. Mine fired just before contact and blew a pretty good hole in my skin. Bled all over. I probably didn't get the full benefit of the shot since some must have run down my arm. I don't see how the covid shot should be any different than a flu shot but then, I've never gotten one of those either. I figure they are mostly for old folks. GD