 [ Symptoms ] is it possible to get gastroenteritis in late july  a couple nights ago i was suddenly nauseous and vomited then went to sleep same thing happened when i woke up morning along with some diarrhea now this morning i was very nauseous and it settled down as the day is going on no crampspainfever is this gastroenteritis [ Disease ] i am not sure what type of std you are referring to but you and your partner had previous partners then this is the source not all people are totally honest about their past sexual experiences how does the std get started if both partners have only been with each other and no one else is it a virus that mutates into an std then infects a person