rat bites happen....blood and all...no big deal if it was....been there ,had that many times...oops...it happens....find a rat 2 days later that we know was eaten ...oops...they hide well....under paper under the ball...I hate that they chew out of plastic tub and the snake foloows them....! ...
.....blood from vent....it happens...but usually after copulations....which takes 9 hours.....
not sure what you have....watch them, check them....
just had a thought...male trying to breed...rubbed the end of the pene or open vent on paper too hard?....check his vent...
...???....we would need pics and that doesn't always help...
snakes can live through alot....should be cool...keep eye on them all...
good luck...
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........JY