I had all-day sickness until 26w with DS1 and was hospitalised with pre-eclampsia at 28w. He was born at 34w. I'd say that was a nasty pg.

With DS2, I stopped work at 16w (doctor's orders) and rested. It was much better. MS stopped at about 18w (funny enough, just after I stopped working...) and I went 9 days over.

HTH!