We had a miscarriage in October and since we have been TTC with no luck. I had a positive test two months ago and two days later I started bleeding and bled for four days then negative tests after that. My periods have been really messed up which makes it hard to track my ovulation. This app says on my best day I only have a 33% chance at pregnancy.. Anyone else getting low chances like that?

I had the Lorena for almost 2 yrs and had to have it removed because it caused me a lot of lower abdominal pain that was unbearable and my strings disappeared and my Dr was.concerned about it perforating my uterine wall after I had it removed I bled 2 weeks straight and then stopped for a month. After that I bled 4 months straight without a day of stopping so my Dr put me on 3 bc pills a day to stop the bleeding, so after 2 weeks of pills it stopped 4 months later in October I got pregnant and miscarried somewhere around 5 weeks and now we are still trying after 5 months it's still not happening.. I'm worried that the mirena may have caused some issues in having a successful pregnancy. Anyone have any advice or had this problem? I have 3 kids from my previous marriage and my fiance who doesn't have any children are dying for a baby of our own....