The Dutchman's position is under scrutiny after another late lapse saw Cardiff claim a 2-1 win on Saturday, extending the Cottagers' wait for a first home victory in the top flight since April 1 in a run which has seen supporters' frustration grow.
"The devil was playing with us. If you concede goals that late, it's awful," former Tottenham, Hamburg and Ajax boss Jol said.
"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, who guided Fulham to ninth and 12th in the last two seasons, is not happy with the jeers.
"That is a problem," said Jol of the boos.
"It's not helpful. That is what always worries me.
"It's bad, it's not good for your health. I've got a thick skin. I could easily say 'b***** off', but I won't do that. It's the reality of the Premier League."
Jol also believes supporters calling for his dismissal should recognise the financial constraints at Fulham.
He added: "I can understand the criticism but they should realise that we are 20th in the table in spending money."
Following a change of ownership, with American billionaire Shahid Khan taking control from Mohamed Al Fayed, there could be more funds available in the future.
Whether Khan will entrust Jol to spend them remains to be seen.
Jol added: "You never know. They could say that you are fine and the next day you are out."