my puppy's belly is swollen and hard and he is having trouble pooping..
Hi There are a few possibilities here. First one is that he's constipated, this isn't terribly unusual in puppies, especially the small or tiny breeds.
If he seems totally happy and healthy otherwise and is eating/drinking normally and doesn't seem to be in pain or distress, then this may be the problem. Check out my A Constipated Puppy page for tips and advice on helping him poop, and preventing further episodes.
However, a hard, distended or swollen belly and an inability to poop could also indicate at least two much more serious conditions...
1. Bloat (aka gastric torsion). This is when the stomach itself 'flips' or twists inside your pup. If this happens a pup or dog will die without treatment, and you'll need to get him to a vet fast. Other signs of bloat include drooling, vomiting, pacing/panting, lethargy, disorientatin etc.
2. An intestinal blockage. Puppies eat all sorts of stuff that they shouldn't and sometimes something gets 'stuck'. This is also a veterinary emergency and can be life-threatening. It has similar symptoms to bloat above.
If your pup seems unwell in any way, then I strongly advise that you have him seen by your vet immediately.