Consult a clinical psychologist. It is better to resolve this issue before it aggravate.

It's a fact that most human beings either think of their past or future most of the time and that's what makes them not enjoy the present moment.Today research has given us proven techniques to handle this,get in touch with a counselling Psychologist, learn the techniques, will work wonders. Also there could be underlying issues ,consult a Psychologist to work through it.

Overthinking about future events brings in Anxiety.. It happens due to some doubt which you have about the future. My suggestion is   do Consult a psychological Counselor /Therapist to get some clarity and understanding about yourself and about your future life..

It is not uncommon to find yourself overthinking about the things that you feel out of your control. These feelings can be very overwhelming which may cause you to overthink and stress yourself even further. From what I can tell, you are afraid of the future because with that it brings a lot of uncertainties that it feels that you may not be able to foresee. I invite you to join a counseling session with me so that we can challenge the thoughts and help reorient you so that you can focus on the future without overthinking.