Is this a red flag? 🚨

My BF and I were recently at a drive thru. He pulled away from the window too fast and forgot my drink. There wasn't enough space to reverse so he had to walk back and grab them from the lady. The car behind us had a group of men who were laughing. My BF assumed they were laughing at him and completely shut down for 30 minutes. We sat there eating in silence while he FUMED. Eventually he started talking again and said he hated being embarrassed and that I did nothing wrong. Still, the whole thing rubbed me the wrong way. Like, why throw a tantrum over something so stupid?