Hm. I'm not sure what to tell you. I had a forgotten tampon one time, I'm sad and embarrassed to say but realized it when I had black discharge and a foul odor. You'd likely have had symptoms of something left in your vagina that would be tell tale signs. And that she removed something, it'd have not been able to be removed if there was something in your vagina. I'm not sure what you removed to be honest. I doubt it is what you think.
It's up to you though if you don't trust your gyno. It's important to trust them. Glad all is well now also with your vagina now object free. Is your IUD still in place?