We had 'night time tantrums' earlier in the year every couple of nights she would have a full blown screaming tantrum (in bed with me) that went for up to 20mins. Weird. Wouldn't let me near her and would get out of bed and sit next to the bed until she eventually calmed down and climbed back in. Not fun at 3am.
Haven't had one for a month or so TOUCHWOOD
No idea what it was, I think they just do weird things around this age, a lot of changes going on. Hope it stops x