Furious speed across carpet, turning back in panic (8)
I believe the answer is:
stampede
'panic' is the definition.
(synonyms)
'furious speed across carpet turning back' is the wordplay.
'furious' is an anagram indicator (I've seen this in other clues).
'across' means one lot of letters goes inside another.
'carpet' becomes 'mat' (a mat is a floor covering).
'turning back' says the letters should be written in reverse.
'mat' reversed gives 'tam'.
'speed' is an anagram of 'spede'.
'spede' placed around 'tam' is 'STAMPEDE'.
'in' acts as a link.
(Other definitions for stampede that I've seen before include "Disorderly rush" , "Chaotic rush" , "Sudden mass rush" , "unstable flight" , "Neat rush" .)