Getting Anxious About Things You Can't Control

meditation music is so helpful because it gives your brain something to focus on. I just look up a meditation playlist on youtube that's like six hours long, and listen to that as i'm falling asleep. And it's been great for me. Somebody said, i usually get really anxious about things that have happened and didn't go the way that i wanted them to,. So i waste too much time thinking about it and getting anxious. Any advice?