It Burns DONT Do This

I got my first razor burn in 55 years. After finishing Shaving with a straight , I found an area on my right side of face still had some stubble. I took a double edge razor with probably an old blade. And went AGTG .Realizing that was a mistake. Also applied a product to prevent burn that had the opposite effect. It increased the burn and rash Latter that night I notice 2 light blisters . What helped was ice packs and applying some coconut oil . In a few days rash and burn subsided. 10 Days latter started to shave again. Never again!