If I may say, what you feel is valid. In fact, very valid at these times. It's part of the COVID-19 anxiety that a lot of people are experiencing.
To tell you honestly, I'm an overthinker as well. To cope, I write essays or poems where I can pour my emotions. Or if not, I listen to music. I suggest Four seasons by Vivaldi if you are into classical, or Mariah Carey inspirational songs if you are into pop. One recent song suggested to me is "Everything Stays" by Marceline of adventure time.
If you need someone to talk to, feel free to message me.

You are strong and you can pass this crisis!