Blue not eating

Blue isn't eating like usual (she usually eats like she's not been fed!). They are both on supa excel. I have also tried science select.

She had her VHD on Friday...could that be anything to do with it?

Is she eating her hay and veg?

I just saw her eating hay. They don't get veg at the moment. They were having spinach which didn't agree with them (although i think it was more barney) so the vet said lots of hay and introduce pellets slowly. Which i've been doing. She's a big girl and usually likes pellets.