Sometimes when i pillar and I move slightly foward, I die from fall damage, even though i am completely on the block and I continue pillaring

Sometimes when I have to get up to high places, I start to jump and place a block underneath me to get higher and higher. Now when I move forward slightly I suddenly die/take damage.

I mainly had this problem in the nether but I have also experienced it on the overworld once. 

I think the problem is when I move forward, the game thinks i fell off the pillar even though I am clearly and the game thinks i fell off.

I just wrote this report because I lost my best survival world because of this bug. I really hope this bug is fixed because its very annoying