She is lively and trustworthy. She has been out of practice for a few months, so this past month, I have been lunging her. Walking, trotting and just recently, short periods of canter. She reacts to voice commands.
Earlier this year, I purchased a new, fitted saddle. I begun to lunge her with the saddle on and she is perfectly fine. She doesn't react badly to it at all. She continues normally. (Last week, I ordered a lunge roller, side reins and a cavesson which haven't yet arrived) I have mounted on her back a couple of times, just for a walk, to get her used to it all again and slowly re-introduce everything. The first time, everything went great. She walked around for a good half hour. She has the tendency to stop and walk backwards. I make her halt and then, ask her to walk forward whilst squeezing with my feet. The last couple of times I have tried to get on her though, something rather different occurred. She didn't walk forwards or backwards. She stands still, looks back at the girth (it wasn't too tight or too loose, I verified). Whilst doing so, she leans back on her back feet and relaxes her front legs until she is about 40 cms off the ground. Then she stands up and repeats it over again. At first I was convinced that it was the saddle, but when I remove her saddle and mount on her again, she does exactly the same thing. Yet the moment I dismount, she stands up and goes back to her normal lively self. I can't tell if she is playing, or if she has back problems. When she walks around normally she doesn't do any of this nonsense and doesn't look back like when I am sat on her back.. (Additionally, she has a bitless bridle so it can't be the bit that is doing this..)Please please help..!