I'm SURE (well, pretty sure) this would have been different with wholemeal flour... It is very possible to overknead a bread dough in a machine, I've been there: Sticky dough without any evidence of the strength and structure that built up along the way. But is it possible to do by hand and if it is, how long will it take to get there?

Useful videos to watch next:

Bread Tip 88 - WHY is My Dough STILL STICKY?

Bread Tip 78 - FIVE signs your Bread Dough is Fully Kneaded - Before and After