It sounds like something is putting pressure on your bladder. Have you been to a urologist? With IC, one typically goes to the bathroom multiple times/day, not just at night.
You can try changing your diet to see if there are foods that cause the pain, as often happens with IC. There's a special IC diet you can try... you can find it here?
http://www.ichelp.org/wp-content/uploads/2015/07/food-list.pdf
The first column are bladder friendly foods, the second column are foods you can try, that may or may not trigger a flare and the third column are foods to stay away from...
You might want to try going to a uro/gynocologist, which is a doctor that specializes in, both, urology and gynocological issues. If your doctor won't try to help find a cause for your pain, I'd definitely look for a different doctor...