Adding a heating pad at a very low temperature can also help. One trick is to fill small plastic bottles with hot water and put them on the puppy's bed, and add the heating pad next to them. With the heating pad, it keeps these bottles warm enough to make you feel like you are sleeping next to another puppy or its mother. If you want to prolong your sleep, try confining the puppy to a larger space rather than a cage so that he can go to the bathroom without waking you up.
Like any newborn baby, when the puppy is small and learns to sleep through the night, they are likely to rejuvenate and energize first thing in the morning. To help your pet achieve the right balance between sleep and awake time, consider training your puppy to sleep by creating a schedule that includes plenty of play, learning, and napping time during the day. This site has a breakdown of the different developmental stages of puppies and offers a list of the most basic things to do during each of which could be useful to you. Sometimes when puppies go outside, they get distracted by the sights and sounds of the world and forget that they are out there for some reason.
When puppies sleep together, they're all in a pack; if your puppy's bed is flat or commercial, it's not cozy for him and is often too big. Most puppies constantly sleep through the night at 3 to 4 months of age until they are ready for a dog bed. Depending on the breed of dog you have, your puppy can sleep between 16 and 20 hours on a 24-hour day. You can help your puppy sleep through the night if you tolerate interrupted sleep long enough for them to grow up.