Spotting on copper IUD smells very bad

So i have been having copper IUD for 4 months. It’s been great even though my period got longer and heavier. However, I’m still experiencing spotting/light bleeding in between my periods and I noticed that this spotting usually smells very bad. TMI, but it smells a little bit fishy, which i don’t know if it’s because of the blood+discharge combo, but it’s very unpleasant. I suspected BV but i have no other symptoms of BV (pain while urinate, colored discharge, etc). Has anyone who has an IUD experienced this? Should i be concerned?