Hi,
Just thought I'd let you know that I had a pretty similar experience to you when I sat the LNAT last year - didn't feel particularly great about the multiple-choice section and ran out of time on the essay. Anyway, I did much better than I thought on first bit and, to this day, I don't know what anyone thinks about the essay. Anyway, after all my stressing I got a place at Oxford, and I'm sure you'll do the same!