TTC recently removed mirena IUD

Hi everyone! I got my IUD removed on October 4th and my doctor said it was safe to start trying right away. I started bleeding on October 5th and that lasted for 4 days and then stopped. The last couple of months I have been getting my period around the 3rd or 4th of every month so I was shocked to see this. But some have said it may not be a period and just bleeding because of IUD removal but for 4 days? Ladies what do you think? I have been TTC since the bleeding has stopped but how do I really know an ovulation date. It’s supposed to be tomorrow if that was a period. Please help!!!