PP insomnia

Mia🐇
I can't fall asleep at night...My baby is 2 months old and will sleep for long stretches sometimes 4-5 hours but I'm so used to being on alert through the night or getting up every 2 hours I can't sleep now constantly anticipating him to wake up. 
Are there sleep medications strong enough to knock me out that won't hurt my Breastmilk somehow?