The pain continues to wrack your body as your bones shift, growing thicker and wider to accomodate your extra mass, your fingers shrink, becoming stubbier and less flexible, your spine contorts, shifting your center of balance to spread your weight across four limbs instead of two legs, your neck and head reshape to better conform to a quadripedal position... your head elongating to better reach the ground...
You are something new, not quite human anymore, but nothing that had ever walked the earth before. Your body has evolved, to acclimate yourself to your new mass, and your new choice of diet. You are now a grazing creature, one content to wander the fields and munch on whatever vegetation you may find.
Speech has not entirely been cut off, yet it is hindered, and you are still in full control of your mental faculties, which you will find once the pain has subsided.