I’m 21 years old male, I struggled from adhd, depression and trichotillomania for a very long time. Couple months ago I started using medicines that helped me to get rid this problems. I’m no longer depressed or suicidal, not impulsive and most important my attention deficit fade away and I can focus on things very well. So when this suddenly happened I felt like “human” first time in my life. But then I started to feel different. Like all my life I live inside my imaginary worlds with no self-esteem and no purpose about life. Now I’m trying to rebuild my life. I’m trying to find things that I can improve myself. I already started to have progress and I feel very good about it. But the thing that disturbs me, I am getting sudden flashbacks about past, like memories or ideas. They are not only bad things it doesn’t matter what am I doing my brain pop up things about that moment, sometimes related to what I do or unrelated about that moment. 
So my question is how can I only focus on today and future. In the past I always lived inside my mind. Yes i achieve to stop maladaptive daydreaming (which was very difficult and exhausting) but still can’t focus on today or enjoy the moment. 
My english is not good I hope you understand me. You can give me any kind of advices for my problems. Thank you