A bit of background: she's 2 years old and we adopted her from the RSPCA back in April. She's settled in really well, and is a friendly active little thing.
She's normally really mad for her food, pestering you to be fed the minute you walk in the door. The last two days though she's been a bit subdued - she normally wolfs her food down in about 30 seconds flat but it took her a few hours yesterday. Today I got home at 2pm and her dry food had been largely untouched since 7am. I offered her a snack and she got pretty excited about it, she then ate most of her breakfast. I went in the kitchen a few hours later to find she'd sicked it all up :( - now she hasn't really touched her tea.
I'm not going to let her out now, so I can see whether she has diarrhoea or is sick again. Just re-reading all this makes me think I've answered my own question - I should take her to the vets shouldn't I?