Pregnancy insomnia

Every night I wake up at a random time and can’t go back to sleep for at least 2-3 hours. It sucks so bad especially since I have a one year old and he gets up earlier in the mornings and I’m so exhausted. I just wish I could sleep through the night. I also get nightmares some nights that are very disturbing and vivid. Anyone have any tips for this. What helped you sleep through the night. I take melatonin to help me get sleepy and to hopefully stay asleep. Doesn’t work through for the staying asleep part. 😫