Sam Allardyce lamented his side's 'nerves and panic' which saw Stoke grab a dramatic equaliser deep into stoppage time.
The Hammers looked to have done enough to battle to victory after taking an early lead through a superb free-kick by full-back Aaron Creswell.
However, after seeing two efforts from Marko Arnautovic ruled out for offside and a header by substitute Mame Diouf hit the post, the visitors snatched a deserved point five minutes into stoppage time when the Austrian forward crashed the ball into the far corner of the net.
West Ham remain in the top 10 in the league, but Allardyce knows their position should have been much more comfortable after witnessing yet another late capitulation from a positive position.
"You have to give Stoke a bit of credit, but from our point of view, we did not play as well as we can," said Allardyce, who revealed that striker Diafra Sakho is set for a spell on the sidelines with a thigh injury.
"It was not about us playing well or not, it was about winning and we had got ourselves into a fantastic position.
"When you are less than 30 seconds away from winning the game and you don't, that is the ultimate blow."
Stoke boss Mark Hughes felt his side had done more than enough to end a run of three straight defeats.
"We are thankful for small mercies, because we did not think we were going to get what we deserved," he said.
"I thought we totally dominated the game and should have won it by a country mile.
"We want to better last season's total and are determined now to get something out of all of the matches we have left."
Sunday Indo Sport