Lucy
The photos are 3 X 1milli second images of a moving object and you ask for comment. It is not really fair on you or the viewers to do a critique.
Herewith 4 web sites which will give you information as to how an English saddle works and how to fit it.
Look up
www.wowsaddles.com www.viva-iberica.com (look for English translation.)
www.fnesaddles.com www.sustainabledressage.net/tack/saddle.php
Spend an hour or so reading what these saddle experts say.
From my inexperienced eye - and I am not an expert saddle fitter - your saddle needs to be checked out by a professional. I personally wonder if it is sitting level and it may be throwing your seating posture out. In two of the photos you are leaning forwards with your weight in the stirrup irons. But how can I possibly tell from a photo?
Lucy nothing replaces the expertise of a trained & experienced saddle fitter. Find one or at least find an old, well experienced english rider.
Barry G