Question Author
Wowzer @ broken glass!
I've just had a good look in the kitchen, and I can't see anywhere where it could have come in. There's no holes anywhere.
The only thing I can think of, is that i do leave the kitchen door open quite a lot, especially when I'm cooking as it gets ridiculously hot, even in December!
I'm starting to wonder if one could have scurried in when it was open. *shudder*
I've moved the dishwasher and washing machine, and there's nothing behind there. I can't move the fridge, cos it's huge, but my dad's coming round in a bit to help me. Oh god, imagine if there's a little rat family living behind it!! *shudder*... again.
I've just read on a pest control website, that you should check behind everything and then, if there's no obvious "gateway", leave out a trap.
So tonight, I'm going to leave out a trap (which my dad is getting from B&Q) with some Peanut Butter on... apparently they like it??
I'll let you know what I find! :-(
Thanks for all the help and advice.