Pregnant with Copper IUD?

so i have had the IUD for about 2 years now and my periods got longer but are never late. this is supposed to be the second day of my period. i had some spotting two days ago, day before my period like usual, but it looked different. brown like old blood. i have had nothing since and no craps which are my main pms symptom. the only thing im feeling is bloating (normal) and breast tenderness (not normal). to be honest i think the spotting was implantation bleeding and my breast tenderness is a pregnancy symptom. i have been pregnant before and had implantation bleed with my last baby and this all just feels like pregnancy not pms. should i just take a pregnancy test now or wait a few more days? should i just go to my doctor now? should i be worried the is an ectopic pregnancy or other complications because the IUD is still in place? has anyone else gotten pregnant while using copper IUD?