You could get an approved saddle fitter to check things for you. This will involve a charge and obviously, if your saddle is too bad, it may mean investing in a new or secondhand saddle that is a better fit.
Ask someone you trust, like an experienced instructor, to recommend a saddle fitter to you, because as with every profession, there are good ones and others who are not so good.
Try to find someone who has been recommended by more than one person - this may take you a little time to find out who's who but your horse will thank you for your effort.
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