Contacts gone from i-phone 4. Help!

Right, think this may be something I've done, but genuinely not sure what. Had a message come up saying "I-cloud settings not recognised" or somesuch, went to retry, think I might have turned off contacts, and selected delete from iphone (you know, as you do). Thought about it, realised that probably wasn't the cleverest thing to do, swtiched contacts back on, hey presto, no contacts.

I'm basically a moron, who is now going to have to ask my friends for all their numbers again, aren't I?

Unless there's a way.....any help appreciated/abuse accepted.

cheers