Our top three guesses for your English dialect:
1. US Black Vernacular / Ebonics
2. South African
Our top three guesses for your native (first) language:
Ye, I knew I be bettah at english than dutch!
also, damn you CC and yer influence.
Among native English speakers of your age and education, you did as well as or better than:
10/10, would ace again.
In all seriousness, I had to think long and hard about this, took me like 20-30 minutes.