the allergy tests should have no lethargic effect on your child but the emotional experience of the uncomfortable skin tests can certainly wear her out a bit. i suspect she will be fine in another day. if she is taking any antihistamines this can make her tired too.
can allergy tests make one year old child tired? . my daughter got skin tests done yesterday for foods that she has had lots of issues with after she was very sleepy the rest of the day and now is acting very lethargic.