Definitely they may be residual symptoms of anaphylaxis
or drug side effect if your all reports are narmal.
But it usually last 5 to 7 days.
You should mention your age, your previous medical history like Diabetes
They are important in guiding you
You should also mention the cause for Anaphylaxis?
If symptoms are persisitng you consult physician get routine blood test
, ECG, ECHO