Quite a bit, when I breed, a message comes up saying that I can't breed for differing reasons, most often because the "pet is busy."  Other times it will say other lines, such as "pet is to young."  However, on all occasions, the pet is not busy nor to young.  If I go back to the previous page and try again, it usually works.  Is this a bug?

Thanks for reporting.

What pets exactly are you trying to breed (pet IDs)? Also can you please write exact error that you get when you try to breed them? We can't debug the problem without precise data, sorry.

Please note that the error message gives you information about both parents, not only about the pet which is active now.

Sorry for the inconvenience.

This is the first time it's happened in a few days. 

When clicking the option "Breed" on my pet(http://beastkeeper.com/pet/102270), to search for public breedings(that's when it's alsways happened, so it can't be about another pet), it told me:

Oops - The Following Errors Occured

• You can't breed pet which is already busy with battle or trades!

My pet is/was not busy with anything.

When I went back to my pet and tried again, it worked.

It happened again, on this pet:http://beastkeeper.com/pet/101004

It wasn't busy or out of energy, and it again happened when clicking on the breed button.

This time it said:

Oops - The Following Errors Occured

• You can't breed pet which is already busy with battle or trades!
• The pet is tired and doesn't want to breed.

I tried again and got the same message, then after I tried once more it worked.

And, another.*sigh*  This pet: http://beastkeeper.com/pet/87792

Everything was the same as the first time except the pet was different, and after going back to the pet and clicking on the button again, it didn't work for several times, but eventually did.

Again:http://beastkeeper.com/pet/99299

Everything's the same as the first time.

Ok, it seems that we reproduced the action sequence which can lead to the same effect. Do you open several pet tabs at once? Like many other actions, right now "Breed" button checks the state of the current active pet, it doesn't automatically changes your active pet when you want to breed it from the previously opened tab. Is this the case? If so, at this moment you can easily deal with it by changing your active pet to the necessary one before breeding. I added this issue to our to-do, so with the next patch we will change the logic to make "Breed" button check for the pet whose profile is opened instead of the active one. Sorry for the inconvenience.

I think that that's what happening, if itsn't I'll post again.:)