Short answer: Please check for typhoid
Detailed answer: Your Doctor gave u the medicines for gram negative infections , thus trying to cover up the typhoid infection.
You will be alright with the same in about 6 more days time but continue with your medicines,
Take A LOT OF PROBIOTICS
Your diet should be curds and rice at this time. No fats, no cereals, no pulses for a weeks time
Get your tests for typhoid after stopping the antibiotics for 7 days.
If the tests are still positive , you will need more treatment.
Also do a stool culture for organisms and what antibiotic would be best for you.IBS
is not what you can get with such a infection.