@oristarA,
The English language had incorporated many foreign words into its vocabulary. I think 'nada' is Polish and 'na' might just be short for 'nada' meaning 'no' or some form of the negative.
The nasal sound in many many languages signifies the negative. e.g. German 'nein', Russian 'nyat', English 'no' Hindi 'nahin', Cantonese 'hmhai' nasal 'hm', French 'non', etc.