I have a very green very babyish new pony and was wondering if anyone has any ideas about an issue we are currently working through.
She's a lovely girl but has a tendency to be silly in her mouth. By that I mean a bit of tongue evading the bit, throwing head around when unsure or not wanting to go forwards. I have put lots of this down to being immature as she does it badly when going downhill (unbalanced I think)
However when going through areas with lots of flies she tends to do it quite severely, chucking her head around, snatching, stamping and mini rearing.
Once the flies have passed she goes back to normal so I'm thinking she's just really sensitive 
She's had her back, teeth and saddle checked and we are also having lessons with an instructor twice per week. She's in a snaffle bit with caveson noseband.
Is there something I can use to stop the flies bothering her so much, or would I be better off just pushing her forward and telling her to get on with it 
Thanks!