Breeding problems with cockitiels?

Question

she's laid about 15 eggs and she still has one that has not been quite laid yet. I think she might be in pain.

Answer 1

She's egg bound and you need to get her to the vet right away!  If she strains for even an hour the shock and exhaustion will kill her.

If you can't access your avian vet right away get some mineral oil and use a dropper or syringe (without a needle) and inject the mineral oil into her vent to help lubricate the egg and hopefully help her pass it.  Then get her into a brooder or small box and put in on a heating pad or next to a heat lamp so she stays warm (about 90 degrees) and calm.

Whatever you do, make sure your vet does x-rays after the egg is removed.  Even a small part of the shell left in her body will kill her.

Why in the world did she lay so many eggs in the first place?  I certainly hope you were giving her calcium and weren't just tossing them after she laid them!