I agree with the others, it will all be up to you how he comes out. the four months of his life are critical in forming his personality, so get him acquainted with as much as you can, with caution ofcourse. Also don't let him walk around or have him interact with other dogs until he gets all his vaccinations. I guess when you go the vet, they can tell you when he'll be ready to interact with the outside. For now interact him with different family members/pets.
I hope everything turns out well and he doesn't have any complications! Think positive and positive things will happen
Keep us updated, can't wait to see pics...