Has anyone had trouble conceiving after c-section?

I’m 16 months postpartum and had a chemical pregnancy back in May of 2018. Never had one before and conceived both my daughters with no issues. (first daughter vaginal birth)

I am currently breastfeeding but have gotten my period back since the end of April 2019. Hubby and I “baby danced” around my expected ovulation time. (11-16th)

I took a pregnancy test around June 22nd and got a faint positive. Kept testing and now they are negative. Period is due July 1st.

Just wondering if it’s normal to have some issues conceiving after C-section? Or if this is something I should have checked out.