IgG positive while NS1 and IgM negative means you had dengue recently and have since recovered. It is possible to still feel symptoms after dengue, and they tend to go away with time.
Next Steps
If the symptoms are severe and persistent or are hindering your day to day life, you should consult an MD Medicine doctor. You need to take ORS because vomiting and diarrhea can cause electrolyte imbalance and dehydration. Do not take it lightly, and drink ORS.
Health Tips
Our bodies need nutrition to fight off infections and recover. Since you haven't been eating well, your body feels fatigued. Plus, you're diabetic which means skipping meals or eating less is even more dangerous. Eat something mild that's easy on the stomach but is still nutritious.
You don't need any anti-biotics for normal diarrhea. Eat food rich in fiber so that the excess water in your stools is absorbed. Fiber gives stools their bulk, and it will help with the diarrhea. Along with that, because you have episodes of vomiting, take an over the counter antacid and sporlac.