I have a couple of questions. Did she void when she was out and did you see that she had? Hard to have a full bladder if you have just emptied it. Don't discount a UTI until you check again. I know (from personal experience!) these things can come on suddenly, as in "I did not have this problem last week!" Also 16 1/2 months could be just about right for "adolescence" to be setting in, so yeah, could be behavioral. Have there been any changes in routine that might "piss her off"? (pun intended!)
As far as moving her from bed to crate, I did that with my two girls back in the day, but they slept together in a chair, with a cover over them. I made the change in summer so they would not be cold, and they didn't fuss too much about it as far as I can recall. Wouldn't have wanted to try it with just one.