I'm playing Minecraft Java Edition, version 1.14.4, unmodded, single player, normal difficulty survival. 

When I start a new world, everything works fine until about 30 minutes into the game. I'll be mining and notice that blocks aren't adding to my inventory anymore (the one that shows carried items, I think it's called the hot bar?). The blocks I mined will come towards me, and make the sound that sounds when you pick something up, but it won't appear in my hot bar/inventory. 

Some people have suggested that it might be because I'm using the wrong pickaxe, or that my inventory is full. Neither of these is the case. I've tried it with my inventory completely empty, and it affects all blocks. I can't even mine sand or dirt no matter what I use to mine it with. I've tried restarting my computer, completely uninstalling and reinstalling minecraft and nothing seems to fix the problem. 

I gave up on it and started playing Minecraft for Windows 10. The same exact problem happened. 30 minutes in, and I can't collect any mined blocks whatsoever. 

The only pattern I've noticed is that the game works fine until I craft a stone pickaxe, usually about 30 minutes into a new game. After I craft it, I can play for about 5 minutes (mining working completely fine), and then all of a sudden I lose my ability to pick up blocks. I can still throw an item on the ground and pick it up and it'll appear in my inventory, but if I throw a block from my inventory on the ground and pick it up, it won't show up in my inventory and will be completely lost. 

Thanks in advance for anyone able to help!