Were is your character? Is he/she in a settlement? Try this, first if your in a settlement. Push the square button on your PS4 controller and enter first person mode then hold you triangle button to get out. We'll start with this. Let me know if that works.
If you can enter combat. Try getting your armor pieces completely Destroyed. Then while still in combat with, who ever. Take some cover and see if you can exit then. If it works, save your game. If that don't work, I don't know. You'll have to use a different save...
Sounds like you got that bug that affects not being able to use weapons, target in vats and whatnot whilst in your power armor. If that's the case you'll most likely have to go back to a previous save. Hopefully you've got a nice back catalog of good save points to go back through. Remember, even though it might feel bad.. it's much better to have to jump back 4 or 5 hours than have to restart the whole game.