8 month old not sleeping since I became pregnant

My 8 month old is still breast fed (and eats solids) especially before bed and what use to be once at night. My suppy still seems to be good but ever since I found it I was pregnant (4weeks) he started sleeping worse and worse and now wakes up every 45min-1hr screaming and refusing comfort of any kind. He will cry for 5 min and then want the boob and then fall asleep. And then we repeat this every hour from 8pm-8am. Let's just say this pregnant body of mine is starting to give out. Any suggestions?!