Receiving the same darkshrine effects in Labyrinth multiple times?

Yesterday i did three uber lab runs and in the last run something strange happened: The first darkshrine gave me an acceleration effect. After i clicked the second darkshrine...nothing happened. That also happened when i clicked the third darkshrine (i also checked the effects when opening the minimap). In the end, Izaro did not drop an additional treasure key, i was not blessed twice and all traps were active. So is it possible that i received the acceleration effect multiple times? Is this a known bug or is there something i miss?

The only one darkshrine effect that you get multiple times is "get blessed twice" meaning that you get 2 attempts at enchanting gear at the end of the lab.
I dont know if it is a bug or not , but its pretty annoying when you get 3 times blessed twice and buff shrine .