My mom doesn't know my boyfriend is the one that got me pregnant??!

Gabriela • First time mom. 23. Due 06.26.17
I have been with my bf for a year. We broke up for 2 months, we were living together and had a lot of issues. Well we got back together because we both love each other we were just not ready. Well now I am pregnant with his kid, and we don't Iive together, he is just leaving his current job to find another one, and I don't have one (I lost mine 2 months ago). My mom is on vacation and she is coming back, and she knows I'm pregnant but she doesn't know it's his. She and him have a terrible relationship, they hate each other a lot. I honestly don't know how she'll react. Any advice??
And yes I know it was a mistake to get pregnant at this moment. Though, his family is very supportive though and so is my mom, she just will hate to know that it's his.
I am 23, and he is 27.
And unfortunately my mom is the type of mom that will scream and get furious and I just don't need that extra stress but I guess I don't have a choice.