(1.6.1) Relog Issue

Alright, I downloaded the Minecraft launcher and worked GREAT for the first login. I shut down the game properly. I re-logined, and I expected to see everything where I placed, except for the mobs.
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When I first played, I placed:
-multiple horses(I really "went to town" with 'em")
-Coal blocks
-some fencing
-Hay bales
-Orange clay
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During my second login, they have been removed. Left behind the hay bales were lighting glitches.
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During my third login (just now), everything worked fantastic, except the horses. about 1/3 of the colts(baby horses) were dieing while glitching into blocks. I saved some of them by pushing them out.

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Overall, everything is working great! Thanks for your time.