Did you breed this ewe or buy in? Any chance of her being with tup? I have a shearling due to lamb end of next week and her temperament has definitely changed over past month or so. She was bottle fed but became more distant once with the flock.
Now she is pregnant she is more chatty with me and likes to come over and have head scratched. I think you will just have to keep an eye on her. Watch for changes in vulva, udder, belly shape, waxing up of teats.