Can't feel my IUD strings?

Alyssa

I got my Skyla in June and I couldn't feel my strings afterward. My gynecologist checked them in July and said they had been pushed inside quite a bit but they were still sticking out. I still havent been able to feel them and I'm starting to think my fingers are just too short. Ive been having sex with one partner without condoms but still haven't felt my strings. Should I be worried? Anyone else have this problem?