I agree it was unprofessional. Unfortunately, I prefer to avoid conflict at all costs so I just left and did my best to avoid both of them for the rest of the day.
I got the stupid assignment turned in. Now I'm too upset and embarrassed to tell him that I finished it, which is apparently what I'm supposed to be doing even though that wasn't communicated to me (overhead from my parents discussing the email).
Honestly, I feel like the adults are talking about me behind my back but just expecting me to know what they want me to do without telling me anything. Like some stupid scavenger hunt that I didn't want to be a part of. I'm just ranting now, sorry. You guys are literally the only people in my life who even so much as give me the time of day.