I have always suffered from severe insomnia and have taken Ambien for years. Just delivered my baby 3 months ago after taking it the entire pregnancy. All Dr's differ on what they want to give but maybe talk to your Dr about natural ways like Melatonin. I am now taking 10 mg every night around 9 and after 3 weeks am just now starting to notice a difference. Pregnancy is different for everyone but usually after the 1st trimester the insomnia eases a bit. Hope you find some relief, I know how miserable it can be.
I was exactly the same when i found out i was pregnant.i found it passed after a week or soon and tiredness kicked in alot.