The Magpies suffered their 13th defeat in 18 games in the form of a 2-1 loss against Swansea City on Saturday.
"Yes, I think it would be damaging for us," the Northern Echo quotes Pardew as saying. "I would like to think we will still secure that.
"I think it is very important [to end the season well]. We are going to have to work hard because we need to really be more resilient in these three games than perhaps we would needed to have been if we'd won."
Newcastle are currently ninth in the table, two points above 10th-placed Stoke City.