Overdo it (2,3,3)
I believe the answer is:
go too far
'overdo it' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for go too far that I've seen before include "Exceed reasonable limits" , "Overstate" , "Overstep the mark" , "Behave unreasonably" , "forget to leave the bus?" .)