Does anyone ever have pain after finally having a bowel movement?

I was finally able to poop a few days ago after close to 4 weeks of not being able to naturally, in between which I only got a little bit out by using an enema. 

Idk if this is TMI but it was like one giant long log and that was it, and it was super painful to get out. Like I had to give up for a bit halfway through bc I’m super malnourished and weak, and it like super painfully retracted back inside of me, and then I was surprisingly able to get it all out in one painful strain with some interesting positioning after that.

The next couple days after that my uterus area would cramp anytime I sat up straight, or walked, or sat on the toilet. Especially when I would try to have another bowel movement. 

Then yesterday I had consistent cramping in my abdomen, and nothing helped it. I thought it might be a stomach virus which stressed me out like crazy because I have severe emetophobia. I made it through the whole day and the night though and assumed that it was just a fluke and from constipation and anxiety. (Just for added context, I have been bedridden with nausea/ anxiety for the past month and I have anorexia and am very malnourished. The past month I’ve been living off of mostly banana smoothies, bread, graham crackers, ritz crackers, salmon, and coconut oil popcorn) 

Yesterday all I ate was popcorn with coconut oil and Himalayan salt (the cramps started after that) and crackers and bread. When I woke up this morning I figured I was fine in terms of stomach flu because I made it through a full day and night but I was still having some cramping. I ate one slice of bread, and my stomach made the loudest most horrid noise and huge rumble immediately after. And it was like my literal stomach, not my bowels. 

Since then, I’ve had worse cramping in my bowels and now my stomach. And I haven’t been able to eat anything. The cramps feel like diarrhea cramps but I haven’t had any diarrhea. (I also haven’t gotten out of bed all day so who knows what would happen if I got up, but I felt so sick when I got up to pee last night that I’m too scared to get up today).

Do you think this could be as a result of that huge poop? Or could it still be a stomach virus? What is going on