what was the critics opinion about it?
It got quite a few negative reviews.
Eh, Eh (Nothing Else I Can Say)
negative review 
what is 'eh, eh (nothing else i can say)'? It is a song. who is the singer? Lady Gaga how did it perform at the charts? It debuted on the ARIA Singles Chart at number 38.
wiki:8684356
Eh, Eh (Nothing Else I Can Say) [SEP] Critical reception
Alexis Petridis from "The Guardian" noted that "Eh, Eh" bears the influence of early 1990s Europop and "is the first song in a long time that warrants comparison to the œuvre of Ace of Base. Matthew Chisling of AllMusic gave a negative review of the song saying "The Fame has 'ballad,' however the breezy 'Eh, Eh' doesn't hold water on this album; rather, it feels dry and lifeless, something which holds this album back". Sal Cinquemani of "Slant Magazine" said that "the breezy island vibe and soft demeanor of 'Eh, Eh (Nothing Else I Can Say)' is hard to buy when sandwiched between songs like 'Poker Face' and 'Beautiful, Dirty, Rich.'" In another article analyzing about the music videos released by Gaga, Oscar Moralde from "Slant Magazine" noted that "Eh, Eh" as a track "is an intriguing case: rather than the tech-assisted sexy-androgynous dance pop that dominates a good chunk of "The Fame", it and its sister tracks 'Brown Eyes' and 'Again Again' are evidence of a stripped-down, simpler, sincere Gaga.