One of our citrus trees was stripped of its flowers by a storm it gave us a few fruit very late in the season. Maybe cause there was so few of them or growing late they made strange misshapen weird fruit. Here is the story complete with pictures and video as usual. http://cappyandpegody.blogspot.com/2016/03/and-now-this.html
Thanks Droopy our blog is full of over 700 posts they are not all gardening but we do love to play in our yard.
It seems like your tree was determined to produce some for you to thank you for all your care you have given it! I imagine the surprise fruit was especially good.