extreme Constipation and period pains

Addie
Ok so Wednesday morning I woke up around 5:55 because I had to go in early for school. And around 4:30 my stomach was hurting a bit but nothing out of the usual, especially since it was 2 days before my period. I could feel it while I was sleeping but like I said nothing unusual. So I get up out of bed when my mom wakes me up and I was having a few pains. Again nothing really unusual. Well they started getting a bit worse. Still not unusual. Then all of the sudden I started feeling nauseous. Like I thought I was gonna throw up or something. I didn't know what was about to happen but I rushed to the bathroom and sat on the toilet. All that was coming out were some lose stools here and there, then the pain would relieve forabout 4 mins. Then they would worsen and I would have a few more lose stools. Then for a bit I wasn't pooing at all. (I'm not trying to be gross) Just screaming loudly with myself hunched over clutching the waist band of your pants area of my stomach. Er.. intenstinse whatever u wanna call it. My mom said I was constipated which I already knew.  I had begun to feel exhausted, and then all of the sudden I started hyperventilating a bit. I began to sweat and I was getting hot flashes now. My pains had stopped for a moment and I was finally able to poo a bit. I felt like I was about to pass out.  Then my pains came back. My mom gave me some mireralax which helped eventually but not for the first 10-15 minutes. I just kept having pains and finally I was able to poo enough for them to stop. My mom had endometris when she was 21 to like 24. Also, I'm only 15. I have gotten pretty bad pains before where I couldn't move and I was on the ground, like in my other post about me possibly catching a bug. But either way it's never been this bad nor have I ever had lose stools before my period. I did talk to my doctor about me having some bad pains and my mom just looks at it like "it's just a phase. I had that too." But not the loose stools and other stuff.  So my doctor didn't give me anything to take. But at this point I am very concerned. If y'all can give me y'all's thoughts on what to do and if it's normal or not that would be great. Thnx.