Your evaporation lines *CAN* be a BFP!

My last period was 2/25. My fiancé and I already have a 3 month old - I was breastfeeding and on the mini-pill. I didn't think this could happen! 
I started feeling the same way I did when I got pregnant with my daughter. I took the first tests last week, it was negative. On Friday (3/17), I took a .88 test. It came back negative, but I left it on the sink. A few hours later, it came back with a VERY faint line. I thought it was surely an EVAP. 
I proceeded to take over 10 tests this weekend. NONE came back positive within the time frame. Only after an hour or so. Last night, I took another .88 test and this one came back quicker (20 minutes), but still out of the time frame. 
I went this morning and bought a Clearblue. It INSTANTLY came back positive!
Just wanted to share my story! Hopefully you ladies don't give up hope!