Yeah, there's something wrong with the sensor that tells the game when you're in the range of the next block to be placed, so if you're too close to the place you want to put a block, it will actually put it on the same space as your head rather than just not place the block like it's supposed to. My best advice is just to exercise caution while building at eye level, don't place a block if it's gonna be placed on your head, and don't build under you. The same lag causes blocks you place to suddenly go back to your inventory due to lag, so you could end up falling in the void.