hi, no doesn't sound like glands at all - one of my other dogs (not a lab) suffers from glands and I have to have them cleaned and checked - yes she licks there a lot when due for clearing but no red mark - could you be mistaking the red mark for something else? - they do lick round that area with glands but the mark is not usual - has it always been there - is it a birth mark - if not, suggest you get checked out for peace of mind