Technically, if you are told to hold 1,000 feet by the tower, then are dropped (i.e. squawk VFR and freq change approved), the 1,000 foot clearance no longer applies once you clear the airspace. Hence, deviating from the 1,000 instruction isn't your concern if you cleared the first ring. However, the 300 bust of the 2nd ring is the concern here.

I had "a friend" bust bravo one time by XXX feet from a departure from a class D satellite airport because he had his head up his ass before realizing what had happened. After dive bombing back to below the shelf he was very humbled and knew that the tower guy had seen it. Nothing was ever said by anyone to this day. But "my friend" did file a NASA report just to be safe.

Things happen to the best of us sometimes. File a report and keep your fingers crossed for a few months. The more time that passes, the more confidence you'll get that you won't be singled out.