Confused

I had the Mirena for 4 years, I had to take it out. I was having complications. I got it removed 3 years ago. Now my husband and I are trying to conceived baby #3. Before I had the Mirena I had a regular period. Now my period it's all over the place. This month I was very sure I conceived. I started tracking my ovulation, I know I ovulate on July 16. But I started bleeding today its more like spotting. My period is due on July 30. Today I'm on 12 dpo. I took a pregnancy test and it's very negative. On 8 dpo I was having a lot of pregnancy symptoms but it all stop at 10 dpo. I don't know what to do.