Had some strange behaviour yesterday, she ate 1fluff and 5 slithers of salmon. She started to twitch, headed to the waterbowl and submerged herself for 5 minutes (constantly moving in circles). On leaving the waterbowl she lifted her tail and gaped her cloaca and pushed four or five times with no result (she did this twice in the space of 3 minutes). There was intermittent twitching for about 7 minutes after that.
She then returned to normal and has been in hiding ever since.
.... I think we're getting closer to a result