It is most likely secondary to procedure and you must ensure you get a patch test
to exclude chemical sensitivities. I presume the 'allergy' was also on the legs.
If you had a similar reaction to waxing before, then it is even more important to exclude the chemical sensitivities before you go through another waxing procedure.
Allergies to steroid
creams are possible and this can also be checked when you have the patch test.
For the time being, antihistamine tablets such as cetirizine
10mg twice daily or allegra
180mg once daily with Calamine
lotion on arms and legs should be enough to control the reaction.
I hope this was useful.