8 dpo boob changes?

JJ
8dpo 3mo pp stillborn at 21 weeks. This is only my 3rd cycle since I lost my baby girl (I had af in December and January) so things are still getting back to normal. This is our first cycle ttc using charting. 
I am trying not to test too soon during the tww, I was very impatient last month and took 3 because I didn't know when af was supposed to come. Af came later than expected last month so it could come anytime now (28 day cycle) but if it follows last months timing could be another week. (34 day cycle) I did not have normal PMS symptoms during either af. But yesterday 7 dpo I had a burning feeling in my left breast. It's a little stronger today. Having no symptoms during previous af I don't know if this is this af coming or signs of a bfp? Before I was pregnant I used to get sore boobs not burning boobs. I also am feeling the pain in the boob that hurt pp when my milk came in. Just looking for some insight. Thanks!!!