I have a 7 week old pom named max who has been eating wet food for about the last 2 weeks - the week before I got him and this last week I've had him. I have started to mix his wet food with some softened up dry food the last couple of days to try to start weaning him from wet to dry food and now he acts like he's having trouble going to the bathroom. Am I trying to do this too early? Please help! He goes to the vet Monday for his check up and shots/worming but I don't want him to suffer till then. What can I do to make him more comfortable?

It is natural for a puppy to become constipated after switching to more solid foods. You probably need to add the dry food a little slower, and only give a small amount once a day for a while.
I don't actually feed my dogs dry food, they won't eat it, they just get a few dog biscuits after they have their canned food.