Long period after IUD

I got my IUD last monday, and after that it's been almost 11 days that i've been on my period. i'm not having any pain or cramps anymore, it's just been a super long period and i'm concerned since mine have never lasted over 7 days. i'm not quite spotting, its almost just a constantly light flow all day each day. have any of you ladies experienced this? should i be concerned? i've been to nervous to even check my strings yet.