Very sorry to hear of the experience of the original poster and wishing their pup a speedy recovery.
I would just like to say that bull breeds can be the most fantastic of dogs and there are many around Dulwich that do the breed (s) proud. It's so lazy, but way too common, to simply label an entire breed (or group of breeds) as 'bad' and another as 'good' but it's exactly this attitude that has led to 1000's of great dogs sat in shelters whilst you can't move for cockapoo's, daschunds, etc. in any London park. It's way more complex than 'good' or 'bad' and inevitably, there will always be well-behaved dogs, and less well behaved dogs across all breeds. The key to everything with dogs is the owners, regardless of breed. Treat your dog well, train it, understand it, and take precautions if necessary (i.e. keep it on a lead).