First time DMSO user

I have been dealing with chronic back pain and a recent slipped rib that has utterly debilitated me. A family member brought me a topical balm of DMSO purchased from Mercola. As these stories tend to go, I did no research individually and applied to my entire back area. Felt intense stinging at first and tried to push through (15-20min), but resorted to a shower. Now I am a bit worried that I’ve jumped the gun, although my back pain has decreased for now. Do I need to be concerned about my skin?