The former Magpies midfielder believes Queens Park Rangers could have got a result at St James' Park on Saturday afternoon.
Moussa Sissoko scored a second-half winner as Alan Pardew's men beat the R's 1-0.
But Barton believes Newcastle were there for the taking, despite their winning run - now extended to six victories in a row in all competitions.
Far from being controversial, the 32-year-old provided more of a reflection on his own side's performances and knows more is expected of QPR in the coming weeks.
"The overriding feeling (after Saturday) was disappointment. We weren’t really at the races," Barton is quoted as saying by the Daily Mail.
"It was an understrength Newcastle side - one that has been in great form - but one we felt we could do a number on.
"We could have done with (three points) in our current predicament. We’ve had a number of great performances of late but we haven’t put as many points on the board as we’d like to.
"We’re extremely disappointed (with where we are) but there’s a long way to go."