Pregnant and stressed and need help

So I'm 12+5 weeks but tbh I don't think it matters. I've been really stressed and hormonal and emotional and all that with it. I have my partner to go through this with but he doesn't talk to me or it seems anyone about when he's stressed he never has until it's gotten too much. Recently he's been taking it out on me with getting pissed off easier and snapping and such and I'm actively trying to help him but trying to keep the stress down is hard. My issue is when I get stressed and upset I can lash out... never anything fully aggressive but that doesn't matter I shouldn't do it. But... the other day there he was pissed off and snapping at me and I think I went to push his arm because he wouldn't listen to me (I'm not sure it's hazy I just know I was upset he was pissed off we were coming into the bedroom) and he like hit me in the stomach and I don't think he realised... it wasn't hard at all just a fucking shock but the fact he didn't notice what he done worries me. It's the first and only time it's happened and I've told him that it won't happen again or I'm leaving but it tells me he might jot be as on-board as he says. I had bad depression and anxiety before pregnancy and it seems to be worse I'd say now but I just don't know what to do. I've messaged his mum as we get on quite well but I'm not sure who else I can talk to all my family are horrible and I avoid contact