Welcome to our community. It is always nice to hear from long-term survivors.
My understanding from my own doctors is that while the risk of recurrence reduces over time, it never goes 100% away. There are a few reports in the medical literature of very late recurrences (e.g., after 10 years) — such cases are apparently so rare that doctors publish articles about them in medical journals. In my own case, I also feel the need to be vigilant in case there are long term effects of the treatments I had. My own view as a patient is I need to be somewhat of a hypochondriac and investigate any instance where I don’t feel well, if only for my own peace of mind.
Many illnesses can involve nausea. Since this is bothering you, I would encourage you get it checked out with your doctor.