seperation anxiety often starts at about this time, so it could well be that.
With my son i used to walk out of the room and then "peekaboo" back if he started to whinge. Id do this as often as required, leaving it a bit longer each time so that he knew that i wasnt goin for long.
With baby CRX she will wake in night whinging and crying if shes got teeth coming, but soon settles. Otherwise she will wake and play and i will leave her to play as shes happy.
4getmenot bought her a lovely pressie at xmas which she has in bed
http://www.leapfrogshop.co.uk/leapfrogshop/sha pes_with_ella.html
it has a day and a night setting, at night it just glows and has a very short piece of music, but wont play which settles her.
Its a stage that most babies will go through, and its hard to know how to deal with it tbh, its a case of trial and error until you find something that suits you all.