Yeah tummy upsets could be from anything, your tummy could just be irritated from something you've eaten. And from what I know, glands in the neck usually relate to something in that general area, ie, sore throat or ear. But your gp is the best person to tell you just to ease your mind.
It sounds like you have come down with something. We're due around the same time (my EDD changed according to my u/s too, but I'm sticking with the latest possible date!) and I have just come down with bronchitis and am feeling shocking. Maybe it's because our placentas have now taken over and our bodies don't want us to get off lightly LOL!
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