He was eating normal and was super happy but after trying some soft dog food he kinda has been weak and he just stays in the back of the bed
Puppies have sensitive stomachs, and sudden changes in diet can sometimes cause issues like mild stomach upset or lethargy.
First, keep a close eye on him for any additional symptoms such as vomiting, diarrhea, or a lack of appetite. These could indicate a more serious issue that may require veterinary attention.
Next, ensure he stays well-hydrated by offering fresh water regularly. Dehydration can exacerbate his discomfort, so it's important he drinks enough water.
Allow him plenty of rest and recovery time. Puppies need a lot of sleep, especially when they're not feeling their best.
Regarding his diet, you might want to switch back to his previous food for now. When you decide to reintroduce the new food, do so gradually over the course of a week. Start by mixing a small amount of the new food with his old food, gradually increasing the proportion of the new food.
Additionally, make sure his bed is comfortable and situated in a quiet place where he can rest undisturbed.
If he doesn't show improvement within a day or two, or if his condition worsens, it would be best to consult a veterinarian to rule out any underlying issues. If you have any further questions, please feel free to ask. Thank you.