Replying to Parties with older people

My friends sister had a party, and they were all 21 or so. I am 18 and drank 8-9 shots, and smoked 3 grams. I was fucked up but everyone asked are you ok? as I stumbled around the house and people were tripped out, my response was "of couse I am ok, don't I look ok?" and I would have a fat grin with squinty red eyes. I was literally forcing my self to keep my eyelids open. Whats the deal with people asking about me being good? Was I really fucked up enough that people though I was going od?