This driver and another black a3 owner were racing through the country roads with extremely loud exhaust rattling the neighbourhood. Spoke to police and handed their car regs over to them. Be aware people.
You were brake-checked because you have an attitude problem, one that causes risk. Even if other people make mistakes that is not an excuse to make the situation much worse, which in my opinion is what you did here. The driver will most likely remember you not as someone aggrieved over their positioning, but someone out for trouble full stop.
You didn't slow down and stay behind because you couldn't slow down. Hint: Slow down.