I'm man 30 year old, got acute diarrhea since 36 hours ago. Its all watery and greenish. Got nausea& green vomiting with slight fever. Pls advise?

Get to your doctor. Today! at best, you are at risk for dehydration, which by itself can cause all sorts of problems.
Sounds viral. As long as you are not having high fever, chills, other systemic signs of inflammation, this should get better within 24-48 hours. Stay hydrated, drinking small amounts of clear liquids often. If you are not improving or getting worse with time, see a doctor.