We went through something similar for quite a while around the same age. Separation anxiety is supposed to peak around now so maybe she's just wanting her mummy a bit more at the moment. Having said that the bruise on the back of her head suggestion sounds pretty plausible to me too, or being a bit overstimulated from birthday & presents etc.

Hope she's back to her usual self soon.
Hmm i hope it's not seperation anxiety i only JUST got her enjoying going to other people, she has seemed fine going to DP etc.
Not sure about the bruise though as she seems fine to lay on my arms or on the couch etc and not be bothered by me touching the back of her head.

I have no idea.. maybe it's cos she looks like she might not be far off walking.. who knows.. it's now 12:30 and she's had all of 20min since 3:30 this morning.