I have a relatively new (4 months) who is an 8 year old warmblood mare, who I have been riding but suddenly foundf she is
bucking, only lightly- not to throw me off when I whip her in trot. She has also now started grinding her teeth, htoeing her head
up and down and yetsrday started wlaking backwards. She has also started wlaking backwards when i try and mount her.
I took her saddle off to check for pressure points or rubs but nothing visible. I had her teeth rasped when I got her as her 5* vetting suggested she had them done.
Any ideas as to whhether it behavioural or she is in pain?

Optional Information:
Pet's Gender: Female
Pet's Age: 8
Type of Animal: horse
Name of Animal: looby lou

Already Tried:
feeling around for any signs she is in pain, have felt by her loin which she puts her ears back at when i touch it and press, but that isnt anywhere near her saddle?