A 3-2 defeat by Newcastle on Saturday ensured that the Baggies remain rooted to the foot of the Premier League table with 13 games remaining.
Tony Mowbray's men did themselves no favours against the Magpies as a series of defensive errors helped to hand the visitors all three points.
With fellow strugglers Middlesbrough, Blackburn, Stoke and Portsmouth all slipping to defeat this weekend, Robinson knows West Brom have missed a glorious opportunity to drag themselves towards safety.
"It was pretty embarrassing and shambolic to concede goals like we did," he said.
"It doesn't help us and won't push us forward to where we want to go.
"We've got to stop these silly mistakes, because it's just not good enough. We know we are better than that and we need to put things right. We've got to be professional about our jobs.
"You can't afford to 'gift' teams goals. When you are playing against quality players, it's impossible to claw the game back. The fact we almost did is because we have got good characters in the dressing room."
UnityRobinson is also aware that, with time running out, improvements must be implemented immediately.
"Now is not the time to let things slip," he added.
"We've worked so hard to get ourselves into a decent position with some good home victories recently.
"Some of the results at the weekend went our way - but they are not going to be like that week in and week out.
"Now we need to stick together as players. We need to pick ourselves up. We've done it before - so why can't we do it again?"