Hi. Thank you for your question and patience. I was checking with specialists as I have never seen this before.   Our guess is that it could be from varying temperatures, growing conditions and something called fasciation.

Fasciation could cause plant parts to increase in weight and volume. There is often a concentration of leaf or flower buds in the area with fasciation. Consider it a plant mistake.
Here is a fact sheet to learn more about the phenomenon - http://msue.anr.msu.edu/news/plants_with_abnormal_growths_the_interesting_phenomenon_of_plant_fascia...

Did the next set of flowers open and seem o.k.?   If you have an opportunity, I would love to see what the plants look like now?  Please feel free to attach new photos. 

Of course you could always remove the deformed buds from the plant. 

Kind regards,
Tracy