Using "wait" for tasks like this is a bad idea.
Imagine there are two power-ups. You pick one, run to another one, which takes you 4 seconds, pick it up. So your superspeed should recharge to 5 seconds, right? However, in 1 second that "wait" from the first power-up triggers and your speed returns to normal.
Or another situation - player hits Menu or Pause button. How do you pause "wait"?
So don't use wait, use Timer behavior instead.