No need to take 3-4 liters liters of water.
2 lit i.e. 8- 10 glasses/day is enough. If you are doing exercise/ heavy activity then needs are raised accordingly.
Nausea due to dehydration is highly unlikely.
Avoid junk, spicy, oily and fried foods.
Next Steps
See a General Surgeon
Health Tips
Stop smoking ( if you are)