Right after my low anterior resection last month, I felt very nauseaus, even vomited, so they gave me medicine for that. Now at home, to help with my low anterior resection syndrome, they Rxed various meds, including one I found out is usually Rxed for patients who have chemo, to help them deal with nausea and vomiting, but I take half the normal dose. An side-effect of that med is that it can "constipates" you, which, in my case, was something we wanted because my stools had turned too watery.
Not as bad as what you've experienced with nausea.