Irvine saw his side slump to a 3-1 loss to Manchester City on Friday, having trailed by three goals at half-time due to individual errors and sloppy defending.
Brown Ideye's late goal proved a consolation as West Brom fell to a fourth defeat from their last five home league outings.
With The Hawthorns quickly emptying late on, the mood at the full-time whistle was downbeat from a home point of view.
Steve Clarke and Pepe Mel both lost their jobs at the helm last season and Irvine knows results need to improve if he is to safeguard his position as head coach.
Asked whether he feared for his job, Irvine told reporters: "The chairman will make a decision as far as that is concerned, I can't control it.
"Can I be confident? Not necessarily, because I don't know what the thinking is.
"All I can do is work as hard as I do and keep on trying to get the right type of performances and the right type of results.
"Unfortunately, in the last couple of games we've attacked well but we've defended poorly and that perhaps wasn't the case earlier in the season.
"We're working hard to try and get the right balance."
City were given an early boost when Ben Foster fumbled Jesus Navas' cross - Fernando opening the scoring as a result - before former City defender Joleon Lescott gave away a penalty soon after.
After Yaya Toure had doubled the champions' advantage from the spot, David Silva capped a quick break to make it 3-0, although Irvine was pleased with his side's improved second-half performance.
"[It was] very difficult to come back in those circumstances," he explained.
"The biggest thing I was interested to see in the second half was whether the players were mentally strong enough and they were.
"That was pleasing because to be 3-0 down against a team of their quality as a result of our own errors was obviously difficult to cope with.
"Full marks to them, they showed their mental strength to take the ball and keep on playing, so I think they deserve a bit of credit for that."
