It's probably not going to show positive on a HPT at 8dpo, I got one 9dpo, sooo faint, and that is VERY early. Implantation can occur 6-12dpo, and if it implants 6dpo, it needs 3-5 days to show positive on a HPT, 9dpo being earliest. I really wouldn't even pay attention to symptoms at all, when we were TTC, every month I wasn't pregnant I had a ton of "symptoms" then the month I got pregnant I was very surprised to find I had NONE, and still don't, 11w5d!