Can a puppy wet the bed?

Generally, dogs don't wet the bed. If a dog wets the bed, it will only do so if it is really unbearable.

as for the situation you mentioned, one is that the training of fixed-point defecation has not been completed, so it will have repeated memories. The other is that it can't find where the toilet is. This requires you to take it for a walk and let it run around the house to form a habit.