If pregnant, can it be normal for nausea to come & go? or would it be constant? if caused by illness, would nausea be constant or come & go? how long would a mild virus like that last?

https://www.acog.org/womens-health/faqs/morning-sickness-nausea-and-vomiting-of-pregnancy In general nausea is common the first trimester-rarely lasts longer. A virus usually would be associated with other symptoms like fever, ,or diarrhea/ cough and lasts 1-2 weeks. If you have burning when urinating may be urinary infection, can cause nausea and should be treated. Call your Ob discuss