Can opk’s be wrong?

[Kelibobs]

According to my opk’s I am 8dpo. I’d had ewcm and cramps for about 4 days prior to the positive opk. Yesterday at 7dpo I got a very faint positive pregnancy test, and today at 8dpo it’s still faint but definitely darker than yesterday. I know it’s very rare for positives to show this early so now I’m worrying about an ectopic! So is there a chance the opk’s were wrong and I ovulated earlier or should I be worried?

In this case I don't think the OPKs are wrong. I would however question your 8DPO calculation perhaps? I temp and do OPKs and quite often I find I ovulated the same day as my peak - so perhaps that's what you've done and you're actually 9dpo? In which case it makes perfect sense to have a faint line already at 8dpo if you implanted early. It's a good thing though, early implantation is far less likely to end up as a CP!