Getting into teen ring, in trouble (8)
I believe the answer is:
entering
'getting into' is the definition.
('enter' can be a synonym of 'get into')
'teen ring in trouble' is the wordplay.
'in trouble' indicates an anagram.
'teen'+'ring'='teenring'
'teenring' with letters rearranged gives 'ENTERING'.
(Other definitions for entering that I've seen before include "Starting" , "Going/coming in" , "Going inside" , "Coming in" .)