hmmmm.....did you check its entire body? could have been a piece of substrate or maybe it did lose a tooth. if its not bleeding anymore i wouldn't worry. just keep an eye on him/her. not sure what else to tell ya..
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1.0.0 arg. b/w tegu
1.1.0 white's tree frog- popeye, jack
0.1.0 southern painted turtle- ms.tortle
0.1.0 crested gecko- crimson
1.0.0 pinto hedgehog- dante