Jol's side lost 2-1 at home to Cardiff on Saturday to leave them in 18th position in the Premier League, with Fulham still waiting for a first home victory in the top-flight since 1 April.
The club's supporters have begun to voice their frustrations but Jol is refusing to panic.
"The devil was playing with us. If you concede goals that late, it's awful," said the Dutchman.
"We are very close. It's not easy to win games.
"I can appreciate fans are getting a bit nervous, or other people. If they invest money in the club, they would like to be in the top 10.
"The only risk I can see is that we will still be near the bottom at the end of the season. I never did that (took part in a relegation battle).
"I feel I can keep them up, but it's not about me."
Jol is used to receiving strong support from supporters having guided the Cottagers to ninth and 12th-place finishes in the last two seasons and he admits he is not happy with jeers from the crowd.
"That is a problem, it's not helpful," he added. "That is what always worries me.
"It's bad, it's not good for your health but I've got a thick skin."