Period then BFP????

Hi! So I had what I thought was a period 12 days ago. It was bright red heavy for a day and then light for two days (like my normal period) but today and yesterday I’ve had positive hcg tests. I have zero symptoms :( and my positive on a strip isn’t really dark. If my last ‘period’ was implantation then I’m 42 days pregnant roughy 20dpo. If so do you think my hcg strip is too light??

Freaking out here :( so badly don’t want this to be a chemical but I fear it is x

A digital test says 1-2 weeks whereas by now I would have thought I’d be 2-3 or even 3+

Any similar stories would be helpful. Good or bad. Sadly I’m a pro at miscarriages now so I fear this is just a tubal chemical :(