Pregnant and boyfriend needs space. Need advice

So me and my S.O has been together for a year. It was love at first sight for the both of us. I found out I was pregnant on April 23, 2017. We both were shocked and surprised because I was suppose to leave for my MEPS with the Navy that following weds. Needless to say our baby was a suprise! My boyfriend has 3 other children with 3 different women. (Please no negative comments) He takes cares of all 3 of his children, loves them dearly and is an awesome father! We were so excited to be expecting. Hoping for a little boy to complete the set. We have been through everything together in such a short amount of time. The day came when I told his mother who was fond of me at the time, and now hates my guts because we decided to keep our baby instead of an abortion. She totally flipped the switch on me, hurt my feelings and is making her sons life miserable as well. She called me on Mother's Day and pretty much told me I entrapped her son and that's what I wanted and she wanted no parts of the babies life. I would never entrap a man with a child! Karma will do its work. Of course It is not true because me and her son made plans that we wanted to be financially stable if we ever decided to have a child. And My dream was to become HR in the Navy. Which is still my goal once I have my baby. I missed one pill doubled up so here I am. So good try on that one mama! He apologized for her behavior and we decided to not let her come in between us. Long story short, 4 months into my pregnancy, no fights, no agruments we were great doing the right thing. He went out there found a second job and pulls doubles like no tomorrow. 4:30am-9:15pm at night, everyday and still managed to see his kids and spend time with me as well. We get into an argument 3 days ago, because I brought up his mom because she treats him like crap and I repeated( pregnancy brain) myself after we had this conversation about his mom that prior Sunday night. "I said you think it's because of me?" He completely shut down on me, I felt like something was wrong so I text him when I got home. I'm a Cancer I feed off of people's emotions and he can't hide them from me. He told me I made him upset about that, I apologized. Next day no response, next day after that I text him are you okay. No response. Friday comes I'm worried. I asked him if he was okay he said he was and I proceeded to say I was worried. No response. I text him and asked if he didn't want to talk that's fine, do you need space, or are you busy. No response. I texted him later after work it's not okay to ignore me you can at least tell me if your busy, you need space, or you don't want to talk. His response I need space.  Most traumatizing thing ever for your love of your life to say that being 4 months pregnant with his child. He's a man of few words but I don't know if I'm overreacting because I'm pregnant or does this mean something? We vowed to not let his mom get in between us but he's upset that I asked him a question about her so doesn't this defeats the purpose? Could it be she's stressing him out and he's taking it out on me? Or he really needs space because of his jobs? Or just in general? I don't know 🤷🏾‍♀️ Is this a break up and I need to prepare myself if it is? or does he really need his space because he's under stress and not telling me? So confused 🙄🤷🏾‍♀️🤷🏾‍♀️
FYI: We do not live with each other at the moment.