Coal blocks disappeared, attempted upgrade to 1.6

I attempted an update to 1.6. I thought it worked, but when I re-opened it, back to 1.5.2
Also I had crafted 64 blocks of coal. Which have now completely disappeared. I know it may not seem like a lot to some people, but that's an investment in time gone. That's a lot of coal to me!
Anyone else have this happen?