I need help with my hyper active 3 year old

My son is 3, he is extremely hyper active. I take him outside to run as much as I can while trying to take care of everything I need and other child. I'm also 33 weeks pregnant and struggling with other stuff.

My 3 year old is very affection and loving.. however he is extremely rough. I have to shield my stomach constantly because he tries jumping on it, pushing it, kicking, hitting, running, flipping. Idk if it's because my stomach is so big or if he's become more aggressive but sometimes he gets me off guard and I feel like I'm going to vomit.

I do not believe in hitting. I've tried talking to him, he understands that there is a baby and he has to be careful but in the moment he just doesn't. He's 3.

I feel myself becoming super short with him and I am almost afraid to let him near me. Even while cuddling or being sweet he pushes really hard.

How can I stop him from doing this without pushing him away and making him feel neglected.but also protecting myself and belly.