Hello Friend, Good that you are seeking a help here. Sound sleep is very essential for both physical and mental health during pregnancy. Consult with your treating doctor to isolate any physical reason. However mentally, it could be due to anxiety caused by overthinking about something in future. Work on some yoga, meditation to mange your mind. If you can't handle it yourself, then take a professional mental health expert to guide. Be positive. You will be alright soon.

Pls consult your gyno and also try practicing some excersice under supervision... along with that do some meditation. Reading good books would help and if please reduce screen time as much as you can