Sammy Ameobi's speculative effort ended up in the back of the net via Papiss Cisse's back and Baggies boss Steve Clarke is downbeat after a second consecutive late loss
Demba Ba's seventh league goal of the season had given the Magpies the lead but Romelu Lukaku equalised after spurning two great chances.
Pardew was happy to see his side on the right side of a last-gasp goal after Ba's own-goal gave Sunderland a draw in last week's Tyne-Wear derby but remained honest in his assessment of the fixture.
"If you shoot you never know what will happen and we've won the game, we'll have to take that because we haven't had many breaks this season," he told reporters. "The goal at Sunderland were perhaps we deserved to win. Today, I'll make no bones about it, we didn't deserve to win but we have.
"We played well in first half because West Brom are a good side, make no mistake. Second half we were tired. Tired physically, emotionally, we had no rhythm. I'm glad to see the back of West Brom if I'm honest."
The Magpies' boss bemoaned his side's performances after their Europa League commitments, and admitted he is still trying to find a way for his team to maintain their standards when they return to domestic action.
"Look at Sundays after Thursdays and we're struggling," Pardew explained. "We've tried different things to get that Sunday performance there and we'll have to try something different next time. Certainly second half, it was a struggle."
Cisse's late winner saw Sammy Ameobi's speculative effort deflect past Ben Foster off his back and Pardew hopes the fortunate goal can kick-start the No.9's form.
"He's important, you know it's very difficult sometimes with strikers," he continued. "In training, he looks exactly the same player, he's confident and smashing goals in from everywhere.
"He's a good trainer but sometimes you have these runs of games where you don't get a goal. That goal will do him no end of help and hopefully benefit us as well."
Ba had to be substituted in the second period, but Pardew was hopeful that the injury would not prove serious for his top scorer.
"I wouldn't say it's a major concern but he's sore," the 51-year-old said. "Whether he can make next week I'm not sure, but I don't think it's an ongoing long one."
Steve Clarke saw his side surrender a point in the last minute for the second week in a row, after losing to a last-gasp Edin Dzeko goal against Manchester City last week, but the Scot insisted that his side deserved much better from the clash.
"A big disappointment again today," Clarke said. "I thought we were terrific, even in the first half we were great, we passed the ball well.
"It's disappointing when you come to a place like this and you're the best team. Not only do we not get a point, we don't get anything and it's really hard to take two weeks in a row but football's a cruel game sometimes and you don't always get what you deserve.
"I've got a good dressing room, I've got men in the dressing room, they understand that some times you don't get your reward for a game. All we've got to do is get the frustration from the last two games and channel that into the next game, we have to take that and get a positive result.
"We've got a good squad of players, I think our performances have been really good, with a little bit of luck over the last couple of games we could have even more points, and we should have more points.
"What hurts me most is the amount of effort and quality my players put in two weeks in a row and we've come away with nothing. They don't deserve it."
Lukaku proved a handful throughout and Clarke, who refused to comment on rumours that the Belgian could return to Chelsea in January, was full of praise for the Belgian.
"When you've got a good squad of players you can't keep disappointing them all the time and Rom's been a good sub for us and he's been patient," he enthused. "Every now and again I have to give him a chance to play, today was the chance.
"I think because of the result it might be looked upon as a negative but I thought the team performance was a positive."