Maybe you should not push it in so far and withdraw a lttle.

being totally serious lads, when a carp has been feeding heavily on bloodworm, they do appear to bleed from the gills and from the mouth, you wash it of an then there is more, but after a min or two when the fish has settled it starts to dry up,,,,just like what you have said...thats what i would put it down too if you could not see any other dammage,

Baz

i have seen this and i think it is carp feeding on swan mussels .As they crunch the mussel shell and blow back all the bits of shell some come out of the mouth and some come out of the gill rakers. If a small piece of shell gets caught in the gill rakers it will rub and cause bleeding. I know this because I have seen bits of shell in my landing net after catching carp.

The spod
I hope this clears it up.