Stuck in Mini End Portal

Upon entering the End and defeating the Ender Dragon, the mini portals begin to unlock in the sky, for each time the dragon is killed, obviously. At first, the mini portals worked perfectly, but as of yesterday, I've tried entering them three times now (Just by throwing an ender pearl into it as always) and my player will become lodged in a pitch black screen. The coordinates jump back and forth from the center of the End's coordinates and those of the Far Lands where I should be teleported. My player cannot move, jump, break blocks or anything; only look around...At black. With no way to die other than starving, I exited the game each time, expecting to come back and my player be in the Farlands, but each time, it ended up with my Realms screen stuck on "Building Terrain" forever. Therefore, I would just leave the Realms and come back to try to rejoin the Realms about an hour later. This time, it would work, but then as soon as I joined, my player "suffocated in a wall" as if I was stuck in the mini End portal. Any help with this would be much appreciated, as I'm trying to cover a whole wall with an End map Thank you, David N.