Tango with a fascinating woman on the last day and get a bit nervous (7)
I believe the answer is:
twitchy
'nervous' is the definition.
(I've seen this before)
'tango with a fascinating woman on' is the wordplay.
'tango' becomes 'T' (phonetic alphabet: alpha, bravo, charlie etc.).
'with' becomes 'w' (abbreviation).
'a fascinating woman on' becomes 'itchy' (I can't explain this - if you can you should believe this answer much more).
't'+'w'+'itchy'='TWITCHY'
'the last day and get a bit' acts as a link.
This may not be right. Some or all of it may be part of another bit of the clue.
Can you help me to learn more?
(Other definitions for twitchy that I've seen before include "Showing signs of nervousness" , "Nervous" , "Jerky" , "in a stew" , "Agitated" .)