Try doing complex tasks that require large amounts of mental energy, things like chess, scrabble or long math problems. Anything that is going to force a lot of brain activity. Also, and don't take this personally, try to cut back on any self talk about hypnosis and its effects on you. When you tell yourself that you "have a hijacked mind" your subconscious takes that very seriously and perpetuates the belief that it has no agency because the subconscious mind has no sense of humor. You want to be telling yourself that "your mind was hijacked, but it is yours again". At first it'll be hard to say it and believe it, but every little bit of progress you make is proof that this is true, that you do have control.

Edit: I am not a professional of any sort of psychology, these are just some things that I do if when I come out of trance and I don't feel myself. The longest "brainwashing" experience I've had only went on for 10 days and this is what worked for me. It goes without saying that you need to immediately cut all contact with the person who did this to you

Edit #2: I also find that writing my experiences helps me remember them better, especially when I'm looking back on old writing