John Rumm wrote:

Only residual now is the occasional itchy feeling near the
injection site, and slight sensitivity on about a square inch of arm if
I go prodding at it directly.

If you haven't had your second shot, mention that to the
injection-person (nurse/doctor/pharmacist). An itchy feeling.

While medical personnel normally laugh off volunteered info,
you never know. They can do the interpretation bit.

Paul