I need someone to listen...

Just a question, has anyone here just feel different after they gotten pregnant? Like they don't know their self ANYMORE? Ever since I've gotten pregnant with my 3rd baby, (which I never wanted by the way it just happened) I have so much worries and I feel so angry all the time. the little things my kids/husband and family do upsets me. I also have this bottled emotions inside me that wants to come out but I'm scared that If I let it out, I won't be able to stop myself and I might end up saying or do something horrible and I dont want that to happen. I get so overwhelmed, hopeless and confused I don't know how to cope with all of it. I'll admit I'm very emotional and reserved person. I can't even open up all of this to my partner, I know he wouldn't understand, He always said he does but does the opposite. I know this is just the pregnant in me acting up. But am I losing it?