Low/moderate dose: the top 1/4 inch layer of your skin feels like it's made out of clouds. You say all the right things in every conversation you have. You want to be friends with everyone. Dancing is the most fun you've ever had. Kissing someone is an experience that grabs you by the collar and screams in your face that you're awesome. Touching soft things is a hard thing to stop doing and touching people is even better. Your favorite person/community is astoundingly, unbelievably, heart-wrenchingly good in every way.
High dose: Your entire body is getting a blowjob. Interactions between people are likely to devolve into hugging, babbling, grinning like fools, dancing, and trying to get each other to come look at the cool thing you just saw or come meet the awesome stranger you just befriended.