Yep, every pregnancy is different from woman to woman, and even in the amse woman from pregnancy to pregnancy.
With my first child I had "morning" sickness every single day. It would wake me up early and I would be stuck inf ront of the porcelain goddess until around 2 or 3 in the afternoon. I would have a mild break for a few hours, but nausea would return in the evening. This lasted into my 6th month.
But my second child I did not have any symptoms at all and never had morning sickness. I found out I was pregnant around 6-8 weeks only because I went to the doctor to find out why I wsn't getting pregnant. I had very irregular period frequently skipping 3-4 months, so couldn't use a missing period as a predictor. But yeah, I didn't have any symptoms with my second baby.