Horrible GI issues while pregnant

An

So I’ve been pregnant 3 times in the last 3 years and with every pregnancy my bowel movements have a distinct smell and anytime I need to go it’s urgent and I get horrible cramps. Almost as bad as contractions during labor. This has happened a few times when I was pp too but mainly when I’m pregnant is when I notice it happening a lot. I will literally sit on the toilet sweating and dry heaving and crying. It hurts that bad. After I go I feel fine. I’m not constipated. My bowels will move easily but my stomach cramps excessively while going and it’s getting to where I’m scared it will hit me when I’m out and about and I won’t make it. Has anyone dealt with this? I have brought it up during my other pregnancies but the doctor said that’s normal but I feel like maybe it’s IBS?