hi guys..really need opinion here..

I have recently graduated and got an interview session last week for medical records executive position..
and stupidly stated oni rm 1.7 k for my expected salary (sigh..too nervous at that time lol)
so now I have been shortlisted for 2nd interview session next week and i'm thinking of demanding for a bit more of my basic salary.

Izzit ok for me to demand for the new expected salary rate?lets say 2.3k?

really need advise here..thanks in advance