The Clarets’ five-game winning streak was ended by Havant as the Hawks left Melbourne Stadium with a 2-0 victory.
The Hawks know if they win their final two fixtures, they could well pip Dartford to the title on goal difference.
Stringer thinks Dartford - with only one game left to play - have a slight advantage and says if Havant do finish second, they would prove to be tough play-off opponents.
“It’s hard to say as a manager but I never really felt my players gave what my sides are all about on Saturday,” Stringer told BBC Essex.
“We never believed in ourselves. Too many of the players were on the edge and never really came to the party.
“We have to be mindful that we had won five in a row. Hopefully, Saturday was a blip but we have to take it on the chin.
“Havant are very mean, they don’t give much away. I think Dartford have that bit of momentum to win the title and whoever plays Havant in the play-offs will have a difficult game.”
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