Pregnancy is not for the weak 😫

I’m 17 weeks pregnant and I’ve been so constipated the entire time. I spend the day at the ER from 11am to 8:35pm because of the pain of being backed up and no bowel movement for almost 48 hours😭😭. They prescribed Mirolax and colace which I had at home but told me to take a bigger dose. All I eat is veggies, fruits, grains and drink water. I have a 30 oz cirkul cup and fill it up 3 times a day it’s all I drink. I do eat turkey and chicken but mainly high fiber meals and vegetables. I’m so uncomfortable. Does anyone else deal with this? This is my third pregnancy and I’ve never dealt with this before. I also walk at least 2 miles a day. What else can I even do???