Hi Sophie,
Easiest way to find out is just ask. Speak to your line manager, tell them that you're aware your contract is due to end but if they're happy to keep you on any longer then you'd like to know so that you can commit to them and not book anything in if they might need you to work. Ask in a way that sounds like you're doing them a favour and they're more likely to give you a definite answer. If they don't, go above their head and speak to their line manager.
And if they don't keep you on, let me know - I'm always happy to introduce people to my business who are hard working and willing to learn new skills!
Hope this helps,
Hannah