Mouth sores before BFP???

Alicia
Hello all!! Need some insight...
I am currently at CD 48, AF is 13 days late. I believe i ovulated on august 31st (heavy EWCM)
Been having on and off symptoms including mild headaches, nausea (no vomitting) bloating, constipation, heavier breasts and until September 29 kept on having BFN
3 days ago, started having an eruption of mouth sores- i must have at least 6-7 of them- and was wondering if any if you ladies had those before getting your BFP??
Scared to test again since all i have been getting are BFN!! 
Any insight is appreciated:)