Sounds like gastro specially with vomiting.
But my pre labour was quite the same was worst with DS1 couldn't go anywhere as I needed the loo and lasted over a month. With DS2 it started again was in tears (can't give birth naturally) so ob decided to get him out early (he was almost 9lb with 10 days to go!) when each of them born the symptoms vanished! Ds3 none (but he was teeny!) except I got contractions very badly before scheduled c section.
I hope you are feeling better soon xxx