Hi I understand that you were treated with Nexito 5 mg every night and now it is increased to 7.5 mg at night. When you took 5 mg you were okay but with 7.5 mg your sleep pattern is disturbed.
Also you drink more water
Next Steps
try to take Nexito in the daytime. don't take it in empty stomach.
Health Tips
avoid alcohol and smoking tobacco. if still you feel the same Consult a Psychiatrist