Ah, wheat bread brings back such fond memories of family kitchens and slow weekends ... Do not worry too much if your dough has not risen after two hours, it happens to the best of us!! Sometimes the room is just too cold, or the yeast was a bit old. If you want to add more yeast now, you can, but please do not just toss it in dry! Dissolve a teaspoon of yeast in a little warm water first, wait till it bubbles up nicely, and then gently knead it into your heavy wheat dough. After that, cover it up and place it somewhere warm like near a sunny window or an unheated oven with the light on. Be patient, wheat bread takes time and love to rise properly!