The critical period is until around the age of seven, right? The reason I'm asking is that I started speaking/reading a lot of English from the age of 8 on, and

The critical period is until around the age of seven, right? The reason I'm asking is that I started speaking/reading a lot of English from the age of 8 on, and as far as I can tell I'm bilingual. Could you explain why that would not be the case, or how that's possible?