Note just disappeared

I had one of my notes just disappear - poof - from my iphone (while I opened it and had no signal...cell or wifi). I opened it - saw the title - clicked it - then a blank note replaced it and I didn't really know what happened - it was that quick. Then I want back to see list of notes and it was gone. It's a very important note - can I retrieve it? This will kill me to lose all those notes on that particular note pad.