Sudden Urge To Urinate (uncomfortable)

I am usually a pretty clean person. I've never had unprotected sex and I have pretty good hygeine. However, I feel the urge to pee randomly. I'll be fine for a while, but then out of nowhere I HAVE to go otherwise it almost hurts to hold it. I'll go it takes a second for anything to come out, and I feel like something is there (not necessarily blocking anything) but its like in the pathway. It's like random surges of pain that range from midly uncomfortable to excrutiating, depending on the day.

I also have a hard time pooping, and it sounds weird, but I feel like they're related. Once, it hurt especially bad to pee, but then I pooped and the pain felt better instantly. I understand I need more fiber in my diet and need to drink more water to fix this, but I don't understand what's wrong. I tried WebMD and looking on google for hours, but no one has posted anything similar.. Help!