Going on 6 months ttc..

Please help, I had a miscarriage or chemical pregnancy recently on June 2nd, I also started spotting the night of june 2nd although I had the positive pregnancy test the same day. So basically I spotted lightly my whole "period" from June 2nd until June 6th. Would this be considered my first cycle after the chemical/miscarriage? Are you more fertile after after? My doctor said to wait a cycle or 2 but we've been ttc with baby number 2 for 6 months this month and I'm in no position to wait any longer. Also how do I calculate when I'm most fertile/ my fertile days, I have 28 day cycles, and I'm using first response ovulation tests. When should i start using them for testing??

Mainly is this considered my first cycle after the fact and are you more fertile during this time??