I would try to be consistent (I know, easier said than done when it's 3:30 in the morning and you just want to go back to bed!
). If you don't want her back in your bed, don't cave in and let her come to your bed (unless that's what you want, but it sounds like you don't want to start that again). She'll eventually get the idea. I found that as long as I was consistent... just went in ds' room, laid him back down, walked out, waited and listened, he eventually realized, 'okay, Mommy's not going to come in and cuddle me/rock me/take me to her bed'. I know that 'just be patient' isn't an instant solution...I remember wanting a magic solution when I was in your boat, but trust me, if you're patient and consistent it will work.
Since you're having these problems at nap time too and, as the previous poster said, she's probably overtired, I would start trying to improve the nap and then things might fall into place.
Could it be teeth?