Thanks for reply.
No, I'm not in creative. Braking blocks is normal, not instant, my inventory is normal (not showing all the items like in creative) and mobs can see and hurt me.
No, I didn't enable cheats when I made this world and trying that command says I don't have permission.
btw, I've noticed something even stranger. When i break dirt, plants, stone...they don't drop but some mod items do drop like Transfer node from Extra utilities.
Not sure if it matters, but I have this survival world, and another one with creative for testing stuff.
I'm afraid I have no ideas then. You might try raising the question on the Curse boards and see if some of the gurus there have some thoughts.