Have a tantrum (5,1,6)
I believe the answer is:
throw a wobbly
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">have a tantrum</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for throw a wobbly that I've seen before include "Become very angry" , "Suddenly blow a fuse" , "Have a tantrum (colloq.)" , "Go ballistic" , "Have a fit" .)