Neither Old English nor Middle English are creoles in the strict sense. The Britons during the Roman Empire pretty much adopted Latin as the official state language, while retaining their various Brythonic dialects for non-official matters. When the Roman legions left to protect other, more important, parts of the crumbling empire, Latin started to fade. Then the Angles, the Saxons, and the Jutes showed up. They tended to keep to their newly founded villages, shrinking from the Roman cities which they thought of as the bones of large and dangerous creatures. When the Normans invaded, Norman French became the official or court language, but it did not replace English. When English again became the official language it had changed greatly and received a huge influx of French vocabulary, but it was basically still a Germanic language. I don't doubt that there were pidgins developed where Normans met with the English to conduct some business, but there is no trace of these, and they do not seem to have turned into creoles at some point.
