Oral - B Pro Science and Pro 3D White Damaged My Gums and Caused Pain

Hello, I bought two Oral-B products, Pro Science and Pro 3D White, about two to three weeks ago. Three people used them, and they literally scratched our gums. We followed the usage instructions carefully, so there is no chance that we misused them. I now have bruising and pain in my gums, making it painful to eat when my inner lips touch them. The funny thing is that during my general dental check-up, my doctor confirmed that my gums were damaged, and I can present all the documents. He even mentioned that such damage is unusual unless the product is too harsh. I bought the product from Migros, and it is an original product. I want my money back.