Could really hot food cut your gum?!
It most likely seared the skin of your gums. If so, then that searing would have caused a blister which would be very likely to burst when you brushed your teeth. I suggest rinsing your mouth out very well with warm salt water and then again with hydrogen peroxide. After that, rinse your mouth out with warm regular water. Do this three times a day or after every time you eat, and soon you should be better and ready to have more tasty food.
I think its more likely that you caused a blister and then in the act of brushing your teeth you caused it to break open and bleed
It makes a blister that bursts and bleeds.
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