Implatantion?!?

Ashley • TTC 2 yr 🌈 Baby

I am 8dpo and I started feeling a bit like butterflies down down. Lower abdomen, not really cramping cause it doesn’t hurt. Lower back pain and nipple soreness not boobs just nipples. When I sneezed earlier today omg it hurt so bad where my uterus is. I took at hpt but got a bfn I know it’s too soon but do you ladies think implantation or aunt flow? I hate that the symptoms are the same