Mistake in the prononciation of surah al fatiha

Assalam ´aleykoum, I think that sometimes I may have pronounce « … na’budu’a… » instead of « … na’budu wa… » in the fifth verse of Surah Al Fatiha. Does that change the meaning? Should I repeat my prayer if I realize this error and the time of the prayer is not over? Should I make up the other prayers from previous days where I may have make this mistake.