IUD question! Please help!

I'm a FTM, I delivered in June, at my 6 week post partum visit I got an IUD (skyla). I've now had it for 3 months with no issues except occasional discomfort and long, but light, periods. Yesterday and today I've noticed horrible nagging pain in the left side of my back and the left side of my uterus/ovary. They're similar to cramps but when I push on it with my hand, like I would with period cramps it doesn't feel normal, like I can't reach it, like it's too far inside for me to reach, so I get no relief. The pain is worse when I sit down or bend over. I just hope it's nothing and that it'll go away, but I'm a worrier and I'm very afraid that either my IUD has moved or I'm experiencing a tubal pregnancy. Any other ladies out there that have an IUD and can relate or help ease my mind please answer me. I love the community of Glow and know I can rely on help and answers.