K.B.
Usually Vic's is not harmful to anyone, and for some it can help a great deal (my daughter LOVES it, and I have used it on her since she was 3 months old and she is a smart healthy 4 year old now). I usually put a dab on my daughter's chest & feet.
With that if there seems to be redness tomorrow feel free to calmly call the ped/doc's and talk with them or a nurse about your concern. It may have irrated the skin but should be fine. If you feel you will sleep better call the 24/7 nurse line either at your childs' ped/doc office or the hospital, it is free and that is what it is there for.