Whenever I create a new portal in the nether and step into it, it glitches (often just generating sky but no movement). I then have to quit out. On going back in, I spawn somewhere within about 500 blocks of home but often high in the air (Resulting in death on landing) or deep underground where I suffocate unless I manage to dig myself out.
I then can use the new portal afterwards to whatever location in the overworld that it corresponds to