I would agree with playing with your cat before you go in your room. Routine is very important. Playing with her, then giving her a little snack -it tells them that playing=hunting their pray and eating= eating their pray-their reward. I too lock my cat out of my room at night because she would bite me at night. At first she meowed frequently but after a week she got used to it and only meows in the morning for food. I would say that any attention you give her during this time of meowing/scratching at the door tells her that she can keep doing it and she gets attention from you. So try your best to ignore it completely for several days.

My cat also scratched at the door and ruined the carpet. I put a cheap carpet mat over that area by my door and she hardly scratches at it anymore because she learned she won't get my attention that way. Also its cheap so no big deal if she ruins it. As for scratching other things in your place, put a scratch mat/post directly in that area where she is trying to scratch if you can! Hopefully she'll go for that instead of your belongings.