How should I feel about my boyfriend/girlfriend being called someone of the opposite sex’s bestfriend?

Anonymous
My boyfriend started a new job only five days ago. Before he goes in, he says to me that he has to be friendly with everyone which is understandable (he works at chic fil a , everyone is nice there)... But today, on only his fifth day, he goes into work and as soon as he walks in the door a girl screams “hey bestfriend!” with a smile. Now in only five days how could they have became this ‘close’ for her to call him that? It made me feel like that little statement he told me beforehand was because he knew maybe he had been being too nice and he didn’t want anything to catch me off guard. However, it did and it actually really triggered me. I know my boyfriend to be very friendly and a people person but I don't know I think this was a red flag. by the way he never mentioned being close or becoming friends with any of the girls there. He only mentioned the guys.
How should I feel about my boyfriend/girlfriend being called someone of the opposite sex’s bestfriend?
3 Opinion