Bonking is when you run out of carbohydrate when on a ride. You go from okay to very tired in the space of about 10 minutes, and you typically get mentally fogged as well. It's possible to do it in a couple hours, but I don't think your description matches being bonked.
Since you rationed your water, it was hot, and you doubled your elevation, I think you just pushed too hard and perhaps got a bit of heatstroke. The prescription is to dial back your exertion a bit, acclimitize to the heat, and make sure you have enough water.