[Stones] CARE: discomfort after surgery?

[Cindy]

A few minutes ago, we heard Sunshine squeak loudly while urinating.  He 
sounded just like he did before his surgery.  He made the noises twice, 
a few minutes apart.

My vet had said we might still hear some squeaks after surgery, but 
within a few days after surgery.  It has been five days, and this is the 
first time we've heard Sunshine sound as though he might be having problems.

Is this normal several days after surgery?

I hope this makes sense.

Worried,
Cindy