I did something really stupid, I was trying to whiten my teeth and first I used the black charcoal stuff which did nothing, then I read that I should try baking soda. After brushing with it my teeth felt oddly smooth and when I looked in the mirror there were two marks on my front tooth, one is small and circular and the other is long and vertical they are yellowish and it looks like the enamel has come away. It is quite noticeable in daylight. I tried to accept what I had done and forgot about it but now I’ve moved to a flat with much more daylight and can see it and have been obsessing over it. Is this something easy to fix?