Not sure if this is a lag issue or similar. Sometimes, when moving my player with the mouse, the sensitivity sometimes goes from not sensitive at all, to "move the mouse slightly and your character spins like a crazy person"

Attached is a video demonstrating the bug/thing. Note through out the gameplay, I was moving the mouse a little bit. Weirdly, due to BandiCam, I couldn't tell what was going on ingame as the game screen rendering froze (the game was still playing however) and I had to drag the MineCraft window around in order for it to render a frame. It luckily managed to record the video though. The sensitivity was set to the default 100%