I have four other children (5, 3 1/2, 2 1/2, 11 months) and am 17 weeks along with my fifth. My partner works 12 hour days and spends 3 more hours commuting, so OH doesn't even see the kids 5 days a week. I can definitely understand feeling like you're doing it alone. Of course kids have boundless energy that we could only hope to ever have. Haha. It is hard to keep up, and I think it's absolutely impossible to keep up throughout much of the first trimester (and don't even get me started on third tri!).
I do have a few tips,... if you don't mind... Watch your child's consumption of sugar and artificial food dyes. If you feed your child, say, sugary cereal with yellow and red food dyes in the ingredient list, you might as well just go straight to bed because your child is going to act out a LOT. It's freezing here right now, but I believe that children should play outside every single day, no matter what. Bundle up, and even if your child only lasts 5-10 minutes before asking to go in (or you begging to go in!), your child's mood will improve vastly! I try to get my kids outside for an hour a day. When it's -7 and a blizzard, that won't happen, but we'll all bundle up and go outside and walk to the mailbox and back (which only takes a minute, while it takes 10 minutes to get them all dressed and gloved and hats on and boots and ready to go out). But they'll stand outside for another 2-3 minutes and catch snowflakes on their tongues or whatever. Then, we'll come in and have some hot soup, or I'll give them a warm bath. I also have a ton of children, but I spend at least 10 minutes straight with each child individually, no phone and no distractions at all, doing whatever they want to do. It means the child gets 10 minutes (or more!) of complete control. If my child wants to do the Hokey Pokey with me for 10 minutes, we do the Hokey Pokey for 10 minutes. If they want to build a LEGO tower, that's what we'll do. If they want to make pancakes (sometimes this happens), I'll pull out the blender (we're gluten free and use oatmeal and make sugar-free, gluten-free, dairy-free pancakes that the kids love!), and I'll let the child measure out the ingredients and press the buttons on the blender. I also think that screen time makes kids act out more. We're kinda crazy, do absolutely NO screen time before 3 years old and the only allow TV once every week (if snowy/rainy) or every other week (normal week). This makes a huge difference in behavior. I notice that my kids act out a lot more if they're allowed to watch TV in the morning or afternoon, so we'll have movie night after dinner once a week or twice a month instead.
And if you read nothing but this one line, I have a mini trampoline that I keep in the living room throughout the winter, and my kids will just walk over to it and start jumping when their energy starts to rise up too high. When I'm feeling okay, and one of them starts jumping like crazy, I know it's time to start moving. I'll turn on a CD, and we'll all dance and sing together. If I'm having a bad morning sickness day or awful energy level myself, I'll just encourage them to JUMP JUMP JUMP! Either way, they have fun and burn off energy. GOOD luck!