Raw food doesn't agree with me either. It's not for everybody despite the general assumption that it's the healthiest way to eat. If your bm habits have changed then your body is telling you that this is not something that it agrees with. I've done juice fasting and a completely raw diet in the past but I've been completely miserable while doing both. My digestion would shut down and my abdomen would be bloated beyond belief.
At some point I came across Andreas Moritz ' book 'Timeless Secrets for Rejuvenation" and there he explains how according to Ajurveda people have different body types and that there is a diet for each body type. I am a vata type, which is air, and the seat of vata is in the colon. Every time I eat raw I aggravate vata, the colon area, which protests by shutting down. Sure enough, I started steaming my veggies and soaking my beans and grains and everything is moving along really well. No more gas and bloating, no constipation.
Give it a try. Take a test online and see what body type you have and feed yourself accordingly.