Why am I in so much pain😭

24 weeks pregnant I'm okay sitting down 99.9% of the time. But whenever I walk it hurts SO bad. I feel like I'm being stabbed over and over again and it's only this bad when I'm on my feet for a few hours. Then sometimes I get this sudden urge to pee like I'm literally about to pee myself if I don't go right then and there. I also keep having sharp pains in the middle of my stomach area. Like directly in the middle. It happens multiple times a day no matter what I'm doing. I just need answers and every time I ask my doctor they say it's round ligament pain. But whenever I look up where round ligament pain happens it's not where my pain is.