My 14 year old cat has undergone a wedge excision of submandibular tumor (AC) with skin flap 12 days ago. Surgery was rather successful, margin was cleared, drain was removed at post op day 6. He started to develop soft swelling (feels like a pouch of fluid) over his wound site and rather noticeably with some tension on the wound. He didn’t seem to be annoyed by the swelling (craving for food as always) and the site wasn’t warm. He was supposed to see the vet in a week time for off stitches. We wanted to consult the vet earlier but he’s out of town, anything we should be aware these couple days? Please help. Thank!