BBT chart and negative pregnancy test

Linda • Tubal reversal in April 2015, miscarriage at 8w3d in April 2016, ectopic at 6w3d in October 2016. Still not giving up!!
Does anyone think I still have a chance? I'm cramping and I feel like AF is coming but my temp hasn't dropped yet. Normally it starts dropping 2 days before AF. All my first response test are negative. 😔