bleeding after toilet?

Niamh • 22 // Music PR
Hi everyone
Sorry for TMI, I was just wondering if anyone had had any similar experiences to me. I have a copper IUD. 
Every other or maybe third month, when I go for a poo (not particularly strained), I bleed like spotting blood? Sometimes heavy sometimes not. 
 It's literally happened like 3 times in the last 4-5 months, and never before that. 
I had my IUD fitted December 2014 so surely it should be fitted and fine by now?
Hopefully I'm not alone 😢
I'm gunna go to the docs but I'm so busy between now and new year I'd just like to have my mind put to rest 😂 you know what doctor googles like!