What is going on?? Tmi!

I posted a day ago about bleeding in between periods. I thought it was implantation because I was 6 dpo but I bled heavy for less than 24 hrs and now there's hardly nothing. I called my doctors and she said because this is the first time it's happened to me I shouldn't be concerned and said if it happens again then I should be seen but I am still worried. I had small clots also so I know for sure it wasn't implantation.