Q. I just started whitening my teeth with 44% carbamide peroxide gel I bought online. I’ve used it 4 times total… once a day for 5 minutes for the last 4 days. After the second use, I noticed my front tooth seemed to be chipped even though I hadn’t hit it on anything. Two more uses later, and the chip seems to be getting bigger. Everything I’ve read online says carbamide peroxide whiteners are safe and the worst side effect is tooth sensitivity, which I haven’t experienced. What is going on with my tooth?! Is it from the whitener??