strange buds

[sept2256]

Dear all,
finally my first cambria in s/h is flowering, but the spike has some problems:

some buds seem growing well, like the first pic, some others have a strange shape (see the second pic) and others died (third one). Could someone help me in understanding what is happening?
te temperature ranges from 20 and 18 °C and the day is coming to be probably too short... may be this is the cause?
thanks!!
Pierangelo