After their fight has ended, both Alexander and Ch'Targh have blood on their daggers. However, while Alexander did manage to slice Ch'Targh on his right bicep, Ch'Targh never cut Alexander. He only struck him with his empty hand.
In the Klingon mess hall, Alexander approaches a table and asks if a seat is taken. In close-ups, he is holding his plate in his left hand and a cup in his right. In the wide shot, he holds his plate with both hands and the cup is already on the table.
Worf tells Jadzia that she must, "present [her] d'k tahg to General Martok as a formal request for him to accept you into our House" at their wedding ceremony. In "You are Cordially Invited," Jadzia needs the permission of Martok's wife, Sirella, to join the house before the ceremony can take place.
The cups of blood wine that Martok and Worf drink from are clearly empty.
Alexander holsters his d'k tahg (dagger) without first retracting the cross-guard.
During the alleged attack (which turns out to be the result of a battle simulation program in the sensors), Martok orders the crew to brace for impact from an expected torpedo volley. All crew members, Martok included, grip their stations and hold fast, all except Worf, who casually stands next to Martok's chair. He did not yet know that the battle was only a simulation. Had that not turned out to be the case, he'd have been in serious trouble.
One of the Klingons mocking Alexander in the mess hall asks if he'd like some blood wine to wash down his dinner, offering Alexander his cup (before derisively suggesting he'd prefer a root beer float). Alexander already got himself a cup of blood wine before sitting down.
One of the Klingons in the mess hall derisively suggests that Alexander might want a "glass of root beer with a lump of ice cream" in lieu of blood wine. What the Klingon is describing is a root beer float, and it is a dessert, not a beverage.