Thanks for the query,
You have developed an allergic reaction
to any product which she is using,
Try to find out that.
It cannot be an infection as you are getting spontaneous cure.
Apply a mild steroid
lotion like hydrocortisone
Also take an antihistamine tablet.
This will give you some relief.
Please meet a dermatologist
for exact diagnosis.
Let me know if you have any other doubt.
you can ask a direct question to me on this forum, following the below link.
Wishing you a good health.