First of all, howling and crying the first few nights can be expected. Your pup will be lonely and scared. They will miss the comfort of their littermates. You can place your puppies crate next to your bed to reassure him if necessary. But only consider doing this if you are planning on having him as a nightly guest when he is an adult.
Stuffed animals with any dangerous eyes etc... removed can be helpful because the pup will have something to sleep next to or on top of like they did when they were with their littermates. Never bring your puppy in bed with you unless you want them their when they are full grown.
If your puppy begins howling at night, you will need to determine whether he is simply lonely or if he needs to go outdoors. If you choose to take him out - do not make a "Play Date" out of it. Simply get him from his crate, take him out, praise him lightly if he goes, and quietly return him to his crate. If you play with him at all he will quickly learn to begin this behavior every night when he gets lonely.
Your pup may not eat or drink a lot the first day or two. This is expected. If they do not begin by the second or third day a call to the vet would be recommended.
Diarhea is not uncommon when they are moved to a new home. The switch in diet, water quality, and the stress from the move can cause this. Their stool should go back to normal as soon as your pet begins to adjust to the new home.