Definitely try more/ different anti-nausea drugs if you can. Don't try and tough it out.
i increased my Dex days from 2 to 3 post chemo. Plus I had pramid, Ondansetron, plus lorazepam for break out nausea. Not recommending these. Just saying you CAN step up your anti nausea a lot, but you need to see the doctor straight away. Don't wait.
I also could have started some drugs PRE chemo day to stop the nausea before it starts.
also I worked out (after way too long) part of my problem was heart burn. So I took drugs for THAT too.
finally I found audiobooks and ear plugs were great for the sleepless nights.
best of luck
L