I would discontinue using this deoderant. It is funny that you have mentioned Lady Speed Stick as someone else I know, shaved and then experienced the same reaction. She was allergic to this particular product.
I would put hyrdrocortisone cream on this to help relieve the irritation. Switch brands and see if this helps. You may have only experienced it on one side if you accidently shaved to close and broke the skin.
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