I don't believe your device is bricked, mine did the same thing too after too many consecutive resets. (Phone battery was dead, plugged into what I thought was a connected charger in my car, and tried turning it on over and over and was like wtf till I realized it wasn't plugged in) Ever since then I get the same triangle and error message on some restarts. If I just reset it again, it runs normally after that error message. Apparently there is some tracker that will automatically display that message after a series of unsuccessful boots, but by no means is it bricked.