Help...door lock stuck

So our double glazed door with 5 lever side locking bar was stuck and for some reason we couldn't lock it. I've stripped it down and graphite lubed the actual locking mechanism and it was working fine. SO next comes the dumb part, I was opening and closing it to make sure and I think I went too far in the lock direction and suddenly it locked into place. No way can I now unlock it no matter what I do if I insert the key barrel either. I'm presuming or hoping that there is something just locked into place somewhere. But try as I might, it will not unlock.

SO here I sit panicking about not even being able to close the door tonight as I can't replace it.
Any help or advice would be most welcome!

See attached pic.

Many thanks.

If it has a double dead lock feature then you will have to trun the key twice.

Thanks for the reply. In the end, out of desperation I took the plunge and stripped it right down. A part off the mechanism inside had broke. I've managed to get it back together and I can now at least shut the door. But thanks.