I wish I could say that mine were less random as they are, but I can't, my emotions are subject to rapid change, sometimes for no reason whatsoever.
I've been laughing with my friends, only to feel everything sink inside me as I hit rock bottom for a few minutes, maybe a day, depending on how much I fight it. I don't show it, not those inner storms that make no real sense to me, but there is no gentle plateau of emotions for me, it's a storm of up and down, sad then happy, loving, then cold, I am rarely one thing for very long.
I can usually shake my head and bring myself back up when it happens in a crowd of friends, but sometimes I really do need to leave because no amount of inner debating or mental shakes can undo this random mood change and I don't won't to infect anyone else with this sickness lol.
Different things trigger me off, one day a song can bring me great joy and be the kind of song you want to dance around your house to, the next day that same song will come on, and make me stop whatever I am doing, because I am battling intense sadness inside.
Mostly I'm happy go lucky, I bounce through my disasters, sometimes I get knocked down and my Fi takes a battering, but I always get back up and laugh about it all.
Am I just insane or do other NF's have extremely varying emotions throughout the day?