Mood Swings

Does anyone else notice really bad mood swings? This is my third pregnancy and I am so tired and miserable all day long. Like awful miserable. And I feel like a terrible mother, I get angry so easy at my 5 and 3 year old and that is not me. Immediately after I yell at them I think to myself what the hell is wrong with me this is wrong, I can't control my mood swings and it's making me super upset. Anyone else deal with this?